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HE work which I now present to the public in 
a printed form, is the result of my observations, 
reflections, inquiries, investigations and re- 
searches for more than forty years ; nearly a fourth 
part of which time has been exclusively devoted to 
It with an assiduity which has almost wholly sacri- 
ficed my social enjoyments of life, and taxed ray raind 
and body to a decree which has greatly impaired the 
vigor of my health, and probably in no small measure 
abbreviated the period of my earthly existence. And 
vet I am very far from being satisfied with uhat I 
have done. I feel that if I could have teu years 
more of health and opportunity, I could greatly per. 
feet the labors of the past ten years. In regard to 
the great principles which I have advanced, and all 
the practical bearings of those principles, I feel the 
most entire confidence, and have no wish for longer 
time to satisfy myself of their correctness ; but I 
think that with more time and labor, I could, in 
many respects, improve the method in which I have 
presented them, and give more strength to the argu- 
ment and force to the illustration. 

My undertaking has, from the commencement of 
my career as a public lecturer, been a most difficult, 
as well as a most arduous one. I have endeavored, 
for nearly ten years past, by oral instruction, to bring 
to the comprehension and understanding of the popu- 
lar and unlearned mind, one of the most abstruse 
and complicated subjects within the range of the natu- 
ral sciences. To do this with any degree of success, and 
to excite and keep up sufficient interest in the minds 
of those I wished to benefit, to make them willing to 
attend to such instructions, I have been compellS to 
exercise all the versatility of power and resource that 
I have been able to command. This of necessity, has 
obliged me to depart widely from that conciseness and 
simplicity of method which properly belonp^ to scien- 
tific reasoning ; and to be at times diffuse in manner, 
and redundant in illustration. And now, I am fully 
conscious that if learned men, of severely disciplined 
minds, do my work the honor to peruse it, they will 
find occasion to complain of the same evils in the 
printed form of my lectures. And my apology is, that 
I have still in view the same great class of people. 
If my design had been to prepare a work for the 
scientific reader only, I should have written it in very 
different style and method ; but nay desire is to carry 
my instruction into every family, anid to be understood 
by every individual of ordinary capacities. And if I 
have not erred in judgment, I have not retained 
more diffhseness of style, nor copiousness of illustra- 
tion, nor indulged more in repetition than the best 
adaptation of such a work to the popular mind re- 
quires. My ffreat object is to have the principles 
which I inculcate, clearly understood. And minds 
wholly unaccustomed to scientific investigations can. 
not readily apprehend the general principles of such 
a complicated subject without a fulness of explanation 
apd illustration, approaching to redundancy. 
But it may be asked, if I intend my work for the 

unlearned reader, why I have not wholly refrained 
from the use of the technical terms of scientific 
language, and expressed myself in terms that every 
one can readily understand ? This is a difficulty 
which I have fully appreciated, and at first, en- 
deavored to avoid ; but I soon found that it would 
compel me to use great circumlocution and tedious 
repetition : and on further reflection, I was satisfied 
that it is best even for the unlearned reader, that the 
technical terms should be retained, and so explained 
that he can understand them. Thus, when describ* 
ing the nervous system, I at first gave a particular 
description of the trisplanchnic nerve (220), without 
giving its scientific name; and in the courseof oneor 
two pages I was obliged to speak of that nerve again, 
and found myself under the necessity of repeating the 
whole description, for want of a name ; and then the 
thought occurred to me, that however well my readers 
might become acquainted with the anatomy of the 
nervous system by studying my book, yet if they 
should take up any other work, in which the tris- 
planchnic nerve, or an^ other part of the human 
system was spoken of m the ordinary language of 
science, they would not be able to understand what 
parts were intended, any better than they would if 
they had never seen a description of the parts. If by - 
any means, therefore, we can make the unlearned 
reader acquainted with the meaning of these terms, 
we greatly benefit him ; for we thereby, as it were, 
teach him the alphabet of science, and greatly increase 
and enrich the furniture of his mind ; which always 
enlarges his understanding and facilitates his attain- 
ments in knowledge. With this conviction, I have 
retained the technical terms of science pertaining to 
my subject, and have endeavored to enable every 
reader to understand them, by explanations in the 
text, and by continual references. Thus in 313 I 
explain the meaning of the terms, organ, tissue, vm- 
cera, etc., and afterwards when I use these terms, I 
frequently refer back to this section. By these means, 
and by the help of a key or dictionary, attached to 
the volume, containing all these terms with a full 
explanation of them, I hope every reader will soon be 
able to come to a clear and ready understanding of 

I have endeavored, as far as I could in such a work 
as this, to follow the plan of Euclid's Elements of 
Geometry : that is, by referring continually to pre- 
viously ascertained principles, or established facts and 
conclusions, whenever they are involved or illustrated 
or alluded to in any process of reasoning, 1 have made 
one part explain and corroborate another, and by this 
means, I have put it in the power of every individual 
of suitable age and ordinary intelligence, by a proper 
degree of application, to attain to a very clear and full 
understanding of my work,.not only in its particular, 
practical bearings, but in its general system of prin- 
ciples as a science. I hardly need remark, however, 
that a work of this kind cannot be read as an amus- 
ing novel, nor as an entertaining narrative or history ; 



but it must be studied, attentively, and perhaps at 
first, with considerable labor, or few will be the wiser 
or the better for the time they devote to it. It is not 
possible that such a work as this, which has required 
the intense mental labor of many years to produce it, 
can be fully compiehended from a single hasty peru- 
sal, even by a well disciplined and much improved 
mind ; and still less, by minds destitute of scientific 
education and habits of close and connected thinking. 
It is, perhaps, proper that I should explain in this 
place, a single point, in relation to my general subject, 
concerning which there appears to have been much 
popular error of opinion. The idea has very fre- 
quently been advanced, that my whole theory in 
relation to human diet, has been founded ^n the 
opinions of Pvthagoras and others who have taught 
that man ougnt to subsist entirely on vegetable food. 
But nothing is farther from the truth than this. I 
had, it is true, read Pythagoras and others who 
subsisted on vegetable food ; but the subject had never 
made the slightest impression on my mind ; and 
nothing was more remote from my thoughts, when I 
commenced my labors as a public lecturer, than the 
idea that man ought to confine himself wholly to 
vegetable food. From the natural turn of my mind, ! 
I had from childhood been given very much to ob- 
servations and reflections and inquiries concerning the 
anatomy and physiology of the human body (550) ; 
but without any other object in view than the grati- 
fication of my thirst for knowledge, and particularly 
knowledge of'first principles, and the relation of cause 
and effect. Being very early in life convinced by 
observation, of the mischievous effects of intoxicating 
drinks, I began while yet a lad to remonstrate with 
my companions and others against the use of them. 
This led me not only to apply what physiological 
knowledge I possessed, but also, to improve that 
knowledge continually, in order to convince others 
of the correctness of my opinions. In June, 1830, I 
was prevailed on to become the general agent of the 
Pennsylvania State Society for the suppression of the 
use of Ardent Spirit. But with my mental constitution, 
it was impossible for me to be satisfied with mere de- 
clamation against drunkenness. I wished to give my 
hearers the reasons why they should not use intoxi- 
cating, drinks. This led me to apply my mind more 
exclusively and diligently than ever to the study of 
human physiology, and finally to animal and vege- 
getable physiology in general : but without proposing 
ta myself any conclusion to which I could arrive, or 
even dreaming whither my pursuits would lead me. 
I was an honest and sincere inquirer after truth ; and 
willipg to receive its teachings and follow where it 
led without waiting to see how it would affect my in> 
terests or my habits. In this manner I was led on, from 
step to step, in my purely physiological investigations, 
and was as much surprised at the discoveries which I 
made, as any have been at the conc.usions to which 
I arrived. 

Having served the Pennsylvania Temperance So* 
ciety about six months, I resigned my agency, without 
any idea of continuing my labors as a public lecturer. 
Soon after my resignation, however, I was persuaded 
to g^ve a course of my lectures on human physiology, 
diet, and general regimen, at the Franklin Institute 
in' Philadelphia ; and before I had completed thia 
course, I received an urgent invitation from New 
york, to visit that city, and deliver my lectures 
there. In New York, I received pressing invitations 
from every quarter; and thus, most unexpectedly 
to me, have I been kept industriously employed in 
this great field of labor, till the present time : and 
my public lecturing, though extremely arduous, has 
by no means been the severest part of my labor. 
Almost every hour of ray life, during the whole time 
not necessanly appropriated to the wants of my na- 
ture — Including many hours that others devote to 

sleep — I have employed in the most intense mental 
application to the great subject which has occupied 
my attention. 

My theory in relation to the diet of man, there- 
fore, has neither been founded on, nor suggested by, 
the opinions of others who have taught that vegeta- 
ble food is the proper aliment of the human species ; 
but' my eye has been continually fixed on the living 
body, observing its vital -phenomena, studying its 
vital properties and powers, and ascertaining its phy- 
siological laws : and wholly without the conscious- 
ness that .any human being had ever advanced the 
iidea that man should confine himself to vegetable 
food ; and wholly without the purpose in my mind, 
of establishing such a position ! But I was unex- 
pectedly and irresistibly brought to such a conclu- 
sion, purely by my physiological investigations. Yet 
when I had thus arrived at this conclusion, and 
began to look about me, and survey the history of 
man, I soon discerned that there were not wanting 
facts, in the experience of the human family, to cor- 
roborate the conclusion to which I had been brought 
by my physiological investigations : and when I 
came to advance my opinions on the subject in pub- 
lic, immediately, on every hand, statements and facts 
and testimonies began to flow in upon me in abund- 
ance. Every one who heard me, and who had ever 
r$ad or heard of anything which corresponded with 
my views, kindly communicated it to me. In this 
manner I have come in possession of nearly all the 
facts and authorities which I have employed in the 
illustration or corroboration ot my principles ; but in 
no case have the principles been drawn from these 
facts and authorities. And it is but just that I should 
add, that many of the authors which I have cited, I 
have not read, but have been indebted to the kindness 
of friends, who have read them for me, and furnished 
me with such extracts as they thought would be 
serviceable to me. In short, I must frankly acknow- 
ledge that I have had much less to do with books 
than with living bodies, in all my physiological in- 
vestigations. I shall not therefore be surprised if 
men of general reading find that many opinions which 
I have advanced as peculiar to myself, have been ad- 
vanced by others, with whom I am unacquainted : for 
my mind has ever been much more given to observa- 
tion and reflection than to reading, and hence my 
knowledge of books is very limited. 

On the subject of anatomy, my attention has been 
more directed to the nervous system, than to other 
parts of the body ; and, therefore, though I have at- 
tended much to dissection and general anatomy, yet 
in preparing my work for the press, I have frequentlv 
felt the want of a more familiar acquaintance with 
the minute anatomy of particular parts, which I had 
before regarded as of comparatively little importance 
to physiology, but which I consider necessary in my 
printed work in order to render it complete. I am, 
therefore, not entirely certain of being perfectly ac- 
curate in every minute point of anatomy, but I trust 
that I have in no case made any great mistake ; and 
I am confident that I have made no mistake on any 
important point. 

In regard to phrenology, I have perhaps said 
enough in the body of my work (532, et 9eq.\ but I 
wish the zealous advocates of that theory distinctly 
to understand that I entertain no hostile feelings to- 
\%ards it. I have aimed not to misrepresent it ; and 
if I have fallen into any mistakes in regard to it, I 
shall be glad to be corrected ; and am ready to em- 
brace it as fully and as warmly as any of them, when 
I can be as fiilly convinced of its truth and import- 
ance as many of them appear to be. .But at present, 
I must honestly confess I have doubts on some points; 
albeit I am not far from a full conviction that, in the 
true science of intellectual and moral physiology^ the 



brain is to be regarded as an assemblage of special 
organs, according to the views of Dr. OaJl. 

Concerning the natural element or elements of mat- 
ter (47) et seq,), its properties and laws, and the pro- 
duction of the various forms of material things, I 
suppose I shall be considered sufficiently visionarv, 
by some ; but it will be seen that I am not wholly 
alone in the speculation ; although I supposed my- 
self to be alone in it, for several years after I em- 
braced the notion, and have, from time to time, been 
not a little gratified to find myself sustained in it, by 
such high authorities as I have since met with (74, 
et teg.). But, whatever may be true in regard to the 
number of natural elements, the great physiological 
and psychological principles which I have advanced 
(522, eiseq.), are, I am confident, irrefragably true : 
and these are all that I wish to insist on, in relation 
to the nature and properties of matter. (105, 106.) 

In presenting my lectures to the public, at this 
time, in a printed form, I feel it my right and duty to 
remark, that it would be verv unjust in the public 
to date their existence from this period. It must be 
remembered that I have been repeating these lectures 
in public for nearly ten years When I began these 
public labors, the subject of human physiology, so 
far as I am informed, had not been named nor 
thought of, by any other person, as a matter of popu- 
lar knowledge and general education : but since that 
time, it has been continually becoming more and 
more a subject of public interest : and now, physi- 
ology and physical education are common topics of 
conversation, in almost every circle. I do not mean 
to imply however that my labors alone have produ- 
ced all this effect. Since I have been in the field, 
several works have appeared both in England and 
America, which have embraced different portions of 
the same great subject. These have undoubtedly had 
much influence on the public, and contributed to pro- 
duce the present state of things. There is one work, 
however, which I believe was published in England 
or Scotland, before I commenced my public lectures, 
and which has probably done more than any other 
one, to excite a popular interest on the subject of phy- 
sical education : but I speak of it only from report, 
as I have never read it, and know nothing of its 
merits, except from the testimony of others, i allude 
to the ' Constitution of Man,* by Mr. George Combe, 
^e first time I ever heard of this work was in the 
summer of 1833, when I was accused of having bor- 
rowed mv views from it. This induced me to foim 
a resolution never to look at it till my own lectures 
had passed through the press. I have adhered to 
that resolution, and can therefore only say, if there 
are views in my lectures corresiponding with those 
advanced by Mr. Combe in that or any other work, 
we have both hit on them without any indebtedness 
to each other. Indeed I lutve seen but few of the 
works which have appeared since I commenced my 
public labors, in relation to the general subject em- 
braced by my lectures, and those which I have seen, 
I have been able only to glance at hastily. Aber- 
crombie*s writings I am wholly unacquainted with : 
and in fact, it is nearly twenty years since I have 
read any work on intellectual and moral philosophy. 

While, therefore, I have gathered all along my 
course such facts and testimonies, in illustration and 
corroboration of my views, as my numerous friends 
have kindly placed within my reach, or selected for 
me, yet all the principles and the main body of my 
lectures, which now first appear in print, have a just 
claim to at least as early a date as 1832. 

In the progress of my labors, however, I have been 
much indebted to many professional and scientific 
gentlemen, of our own country, for numerous advan- 
taees and facilities which have been greatly service- 
able to me ; and were it proper, I would gladly name 
several gentlemen of the medical profession in Phil- 

adelphia, New York, Boston, and other places, whose 
inany civilities and favors deserve and receive my 
sincere acknowledgments, in this place. It has ever 
been a cause of deep regret to me, that there has been 
so extensive a misunderstanding on the part of many 
members of the medical profession, in regard to the 
character and tendency of my labors. And now I 
can only assure them that I entertain the highest 
respect for the profession. It is certain that without 
a well-educated medical profession, of high moral 
tone, society cannot prosper ; and it is equally certain 
that such a profession will be most accurately estimated 
where society is most intelligent Jn regard to the pro- 
per qualifications of such a profession ; and therefore 
the most certain means of destroying every species of 
medical empiricism and imposture, and of securing 
the highest confidence in a responsible profession, is 
to enlighten the people in the knowledge of the laws 
of life and health. 

In all my public labors I have carried with me a deep 
and solemn sense of responsibility, which has at times 
almost overwhelmed me. Most conscientiously have 
I desired, and sought to find out the truth, for the 
truth*s sake, and to promulgate it for the good of 
man.^ With the same deep and solemn sense of re- 
sponsibility, and that same conscientious purpose of 
soul, I now present this printed work to the public. 
If I believed it to contain any mischievous error, God 
knows I would not send it abroad, to do evil in the 
world. Yet I am but a human being, and with all 
my sincerity of purpose, and untiring diligence to 
ascertain the truth, it is possible I may have fallen 
into some mistakes ; and this consideration has led 
me to refuse to have the first edition of this work 
stereotyped, because I wished to have the opportunity 
to correct any errors that might be pointed out : and 
therefore, 1 now sincerely and earnestly entreat all 
medical gentlemen and others, for tbe sake of truth 
and humanity, to examine this work critically, and 
to expose every error they may discover in it. If 
they attack it with ridicule and vituperation, I shall 
have no confidence in their honesty, but will never- 
theless endeavor to be benefited even by their abuse : 
but if, in a manner which evinces an nonest disposi- 
tion to serve the cause of truth and humanity, they 
point out its errors or its blemishes, I shall gladly 
and gratefully receive their corrections, and apply 
them to the improvement of my work 

Many good people, have entertained the idea that 
the dietetic docirines of my lectures are contrary to 
the Sacred' Scriptures, and that the promulgation of 
them is unfriendly to religion. The fears and preju- 
dices of such people, however ill founded*, are to be 
regarded with respect, seeing that they spring from 
those elements in the mental and moral constitution 
of human nature, which, when properly exercised, 
lead to the just regulations of society, and on which 
the correctness and stability of all good institutions 
among men depend. I wish, therefore, to assure 
such people and all others, that I have not been un- 
mindful of these things, but have thoroughly ex- 
amined them. It was not suitable that I should in- 
clude the results of my investigations on these points 
in such a work as this ; but I have another work 
nearly prepared for the press, in which I have enter- 
ed extensively and felly into a careful examination 
of every point of relation between my lectures and 
the Holy Scriptures. It is my purpose to pre- 
sent that work to the public as soon as possible ;* 
and I trust it will wholly satisfv every honest and 
conscientious mind, that there is the most entire bar- 
mcmy between the Sacred Scriptures, and the diete- 
tic and other principles taught in this work. 

NorthamptoHt February, 1839. 

* It has since been published, and should drcomstaaoes 
Justify, we may issue an English edition of it some time.— E». 


LscTVES I.— Man's relation to the world— The tme mode of 
studying the philosophy of man— General ignorance in regard 
to all the constitutional laws and relations of human nature — 
The causes of this ignorance— The means of remoring it, etc. 

II.— The nature, origin, primordial forms, and properties of mat- 
. ter — The yarious forms of matter in the inorganic world— their 
origin — their laws of constitution and relation, etc. 

III.— The relation of organic bodies to the inorganic world— The 
origin of living bodies— The properties and powers peculiar to 
liring bodies, and common to all organ|xed bodies, vegetable 
and animal— The properties and powers peculiar to animal 

IV.— The scTeral materials composing the human body— The 
three general tissues of the body— their nature and properties— 
and their general distribution in the construction of the body. 

v.— The nervous system of the human body— The nerves of 
organic life— their anatomy and physiology— their distribution 
to the several organs— their relation to the general ftmctiohs 
of the vital economy— The c««bro^pinal system of nerves— its 
anatomy, physiology, etc. 

VI. — The anatomy of the brain— connexions between the nerves 
0^ organic life and the c^rebro-spiual system — ^The physiological 
relations between these two systems — their reciprocal sympa- 
thies, etc. — Sympathies between the body and the mind, etc. 

Vir.— The particular anatomy of the several organs and parts of 
the human body— and their general arrangement, and design 
inihe system, etc. 

VIII.— The physiology of the human body, or the particular 
functions of all theorgans of the system, in the production of 
all the effects and phenomena of life— sudi as digestion, secre- 
tion, absorption, circulation, nutrition, respiration, etc. 

IX.— The nature of the human soul— Its wlation to the brain^ 
The diversities of human character— Phrenology— Intelleetoal 
Physiology— Mental sanity and insanity— Causes of Insanity, etc. 

X. — Moral phvsiology— The moral powersof man— Their relation 
to his organic and animal nature, wants, instincts, depravities, 
etc. — ^Tlie nature and powers of the conscience— On what its 
correctness and incorrectneiss depend, etc. 

XI.— The power of the human constitution in relation to the 
duration of life— Primitive longevity of man— By what mekns 
human life has been abbreviated— Pr^ent capabilities of the 
human constitution — By what means youthfulness is preserved, 
liie prolonged, and healthy and happy old age secured. . 

XII. — Constitutional laws of relation between each and every 
organ, substance, and property of the human body, and between 
each and all these and every external substance on which the 
human body depends, and by which it is affected— Relations 
of the great organs of special sense to the properties of external 
things — Relations of the organs of smell and taste to the respi- 
ratory and alimentary wants of man— Relations of the teeth to 
the nature and condition of food— of the skin and lungs to the 
atmosphere— of the stomach to the qualities of food — of the 
senses of hunger and thirst to the dietetic wants of the vital 
economy, etc. 

XIII.— The simpler, plainer, and more truly natural the food of 
man, the better is it adapted to all his physiological and psycho- 
logical interests— This proposition illustrated by the general 
history of the human family, fh)m the earliest times to the 

XIV.— The evidence of comparative anatomy in relation to the 
natural dietetic character of man — the versatility of the physio- 
logical powers of the digestive organs of man and other animals 
—Relation of reason to instinct— Why the average longevity of 
man is nearly the same in all climates, situations, etc.— The 
true elements of physiological reasoning in relation to the natu- 
ral dietetic character of man. 

XV.— Physiological evidence in relation to the natural dietetic 
character of man, derived from the comparative effects of ve- 
getable and animal food in the development, size, symmetry, 
and beauty of the human body. 

XVI.— Comparative effects of vegetable and animal food on the 
human body with reference to suppleness, agility, vigor, ability 
to endure protracted effort, etc.'-Physiclogical principles ex- 
plained and illustrated by facts. 

XVII. — Comparative effects of vegetable and animal food in 
enabling the human system to resist the action of morbific and 
I>e8ti1ential causes, and to recover fh)m disease, etc.-'^nd with 
reference to longevity, prolificness, and the ability to endure 

XVIII.— Comparative effects of vegetable and animal food on 
the sensorial power of the nervous system— partictilarly on the 
special senses and intellectual and moral faculties ; — and with 
reference to insanity. 

XIX.— Comparative effects of vegetable and animal food on the 
animal propensities and moral sentiments and actions ; and on 
the cerebral development— General conclusion from the ana- 
tomical and physiological evidence in relation to the natural 
dietetic diaracter of man. 

XX.— Animal food— flesh, fowl, fish, butter, cheese, milk, eggs, 
if used at all, the best kinds and qualities, and how best pre- 
pared, etc. 

XXI.— The rich and bountiful supply of the vegetable kingdom 
for the sustenance of man— The great physiological principles 
in relation to the preparation of vegetable food— Bread and 
other articles, how best prepared. i 

XXII. — ^The proper times of eating, and frequency of meals— 
The physiological principles explained and illustrated. 

XXIII. — The quantity of lioiDd necessary to sustain the human 
body— The natural drink'of man— The pure stimulants, salt, 
pepper, mustard, etc., tea, coffee, alcoholic liquors, tobacco, 
opium, etc.-'^eir effects on the system. 

XXIV.— Sleep, iu physiological philosophy— proper time and 
quantity— Beds, the proper kind— Bedclothes, the proper kind 
and quantity— Bedrooms, Bathing, Air, Clothing, Exercise, 
Voluntary Evacuations. 


Han's raUtioiif to tha world— Trua mode of studying the philo- 
sophy of man — Man's ignorance on the subject of life, health, 
and disease— In regard to erery thing else he will acknowledge 
first principles, fixed laws— He contends that every thing con- 
cerning life, health, and disease, is uncertain and contingent— 
This ignorance of the laws of life, etc., accounted for— Disease 
leads to the study of remedies rather than causes— The essence 
of life unknown— How its laws are ascertained— Extensiveness 
and comprehensiveness of the science — Requires the most 
serious and x>erseverlng application of the mind. 

1. Mak 18 the 8oal of the world — ^the intellectual 
and moral sensorium of nature. 

He is not, indeed, the creating cause of thingg, nor 
18 he the efficient energy by which the various opera- 
tions of nature are carried on. He does not sustain 
thlB sun in his bright sphere, nor cause the light and 
heat to come down upon us as an all.pervading spirit. 
He does not wheel the planets in their eternal rounds, 
nor roll the earth upon her axis, nor urge the moon 
along her silent way. Nor does he heave the ocean's 
tides, nor pour the streams and rivers from their 
fountains, nor direct their currents in their winding 
paths. He does not clothe the earth with vegetation, 
nor embellish it with verdure, and the various hues 
and tints and forms of beauty, nor fill it with rich 
fragrance and delicious fruits. Nor does he quicken 
this magnificent theatre of being with the number. 
less forms and modes of animal existence. Yet, but 
for man, to what great intellectual and moral end 
would all these things exist ? 

2. The grazing ox might crop the grass, and, for 
all the purposes of his nature, instinctively discrimi- 
nate the odors of the earth, and slake his thirst in 
the clear stream ; and, when the summer's heat be- 
came oppressive to him, he might seek the cool shade 
of the forest ; and, in his ruminating moments, he 
might raise his head, and on his unenquiring eye the 
sun or moon, or the far distant star, might pour its 
light r but neither the herbage, nor the fragrance, 
nor the varied hues of the vegetable kingdom, nor 
the beautiful freshness of the morning, nor the noon- 
tide splendor, nor the soothing silence of the summer 
twilight, nor the magnificence of the nocturnal fir- 
mament, nor aught of creation's loveliness or sub- 
limity, would awaken in him the deep musing of 
philosophic thought, or moral feeling, or reflection. 

3. Not so with man ! He opens his percipient 
faculties on the surrounding world, and light with 
its variety of hues and visual properties of external 
things, and the various odors of the earth, and all 
harmonious and discordant sounds, and the qualities 
of taste and touch, rush in and make their impres- 
sionsupon his intellectual and moral sensibilities, 
and awaken there the elements and energies of mind 
and moral feeling. And thus 'all substances and 
qualities and things surrounding man become to him 
the great alphabet of knowledge. The numerous 
properties which inform his senses, seem to come in 
as with intelligence to inspire his intellectual opera- 
tions, and to constitute a part of his own mind ; and 
he throws out his thoughts and feelings over all 
things, and associates and sympathizes with them, 
till he becomes, as it were, a part of them, and they 
of him, and until he learns to arrange these various 
elements into systems, and elaborates from them the 
profound truths and principles of science ! 

4. The beautiful, the harmonious, the sublime, 
associated with external things, are but the inward 
sentiments of his own soul, awakened by those things 
and breathed out upon them, till they become, to his 
imagination and his feelings, invested as with an in- 
.tcUigisnt and sympathizing spirit, which holds com- 

munion with him in his various moods of mirth and 
melancholy and poetic musing and solemn meditation. 

5. The mountains and the valleys and the streams, 
the deep forests and the spreading lawns, the 
ocean's foaming beach, the craggy cliff, the thunder, 
ing cataract, and all other things in nature, are en- 
dowed by him with their peculiar genii, and become, 
as it were, the talismanic keys which awaken their 
appropriate tones and melodies and strains within 
his breast. And thus he grows in knowledge and 
wisdom, and in moral character, and erects an im- 
mortality of thought ; and makes all material sub- 
stances and forms and qualities inservient to mhid. 

6. He lifts his eye to- the heavens, and beholds the 
sun and moon and myriads of stars, whose light de- 
scends upon him like an informing spirit ; and he 
diligently contemplates them till he learns to weigh 
them in his balance, and measure their dimensions 
and their far-sweepbig orbits ; and ascertains their 
laws and their relations ; and finds the universe to 
be a vast fraternity of material forms, and feeh him- 
self to be the percipient and intelligent centre of 
material things, gathering their influences and con- 
verting them to mind, which he exerts upon them, 
and by which he investigates their nature, qualities, 
laws, relations, purposes and ultimate designs. 

7. Thus man becomes a part of the vast world in 
which he lives, and every thing becomes a part of 
him ; and hence it may with propriety be said that 
man is the soul of the world. Nor is he only thus 
intellectually and morally associated witll ibaterial 
things : his wonderfully constructed body, the orga- 
nic tenement and engine of his mind, partakes in its 
elements of their common nature, and is subject to 
those conmion laws of matter which bind all forms 
together in inseparable relations. 

8. Whatever, therefore, may be the interest con- 
nected with material thiiigff, nlan is the centre of 
that interest ; and conseqiiently man, in his nature 
and faculties, and capabilities a«id condition, and in 
his relations to the world in which he exists, is one 
of the roost interesting and important subjects which 
the human mind has power and compass to investi- 

9. But it is a profound and complicated subject. 
An attempt to «tudy living man either as a subject 
of intellectual, moral, teligiolis, political, physiologi- 
cal or pathological science, singly, without a' just re- 
gard to his peculiar nature and constitution and 
condition, the laws of relation under which he exists, 
the reciprocities and mutual dependencies of mind 
and body, and the various influences which act upon 
him, as a materia], organic, animal, intellectual and 
moral being, would almost necessarily result in error. 
And for this very reason the world has ever been 
filled with controversies and disputes concerning man 
as a subject of intellectual, moral, religious and poli. 
tical philosophy. Volumes without number have 
been written on these topics, of a strange mixture of 
truth and error, mainly because the investigations 
and discussions have been conducted on partial and 
improper grounds. Nor have they who have studied 
man as a subject of natural history or of physiology 
and pathology, wholly avoided the same sources of 
error and absurdity. 

10. If we would know the true philosophy of the 
human mind, it is not enough that we, as metaphy- 
sicians, study man's intellectual faculties and capaci- 
ties and laws ; but we must ascertain how far the 
mind is connected with the body, to what extent it is 
affected by the conditions of the body ; and then, 

•-•".T — r- JinrnTT, — 


again, on what depends those conditions of the body 
which affect the mind. In order to this, the body 
itself must be understood in its animal and organic 
nature, and its. physical and vital properties ; and 
laws, in its physiological actions and pathological 
affections. And this investigation will disclose to 
usr a mnltitude of relations between human organic 
^ife, and the animal, vegetable and inorganic world 
purbund us ; relations which not only greatly affect 
the body, but, in the present state of being, modify 
mjind and morals and religion to an extent which 
cannot safely be disregarded. 

11. ^ So likewise, if we would correctly understand 
the science of physiology or pathology, we must take 
Into view, and thoroughly investigate, the whole na- 
ture and condition and relations of man. He who 
greats of the functions of the human organs, and the 
di^ases of the human body, without fully and accu- 
rately considering the modifying influences of the 
mind, and of the various physical and moral circum- 
itaoces acting on the healthy and on the morbid 
sensibilities and sympathies of the system, may in- 
deed form a theory which will have its day of popular 
acceptance ; but fortunate without a parallel will it 
be, if it does not, sooner or later, prove to possess suf- 
flcient errors to sink it into utter disrepute, if not 
into total oblivion. 

12. There is probably no subject which the mind 
of man has ever contemplated, concerning which 
more extensive and enormous error prevails, than in 
regard to human life and health and disease ; and 
yet nearly every person seems to think that there is 
a kind of intuitive knowledge possessed by all, which 
^nables each one to understand his own constitution 
and what is good for him, better than another can 
teach him. 

' In relation to almost every thing else in nature, 
mankind are willing to acknowledge that thereare 
fixed prindples and permanent laws and established 
prder and system. 

; 13. If we speak of the science of astronomy, and 
lusert that Qod has constructed the planetary sys- 
tem upon fixed principles, and arranged the several 
bodies according to precise laws, — ^that the relative 
size, weight, distance, velocity, and every thincf else 
in regard to the whole planetary system, are regu- 
)ated and governed by the most exact and permanent 
)aws, — everyr enlightened christian and theist will 
readily admit the truth of the assertion. 

Or if we affirm that, in the creation of our globe, 
God ordained all things accordingto fixed principles, 
and that he has established unchanging laws which 
govern it in every respect, our affirmation will be 
promptly acceded to. Or if we speak of the science 
of chemistry, and declare that all the molecular com- 
binations and arrangements of matter are according 
to fixed laws, and that these laws always govern 
ever^ chemical action and result with the utmost 
precision, here again the truth of our declaration 
will be acknowledged. If also, we assert that God 
has constructed every mineral according to fixed 
principles — that the formation of every crystal is 
governed by established laws, this too will be admit, 
ted. If we proceed yet farther, and afiirm that, in 
the vegetable kingdom, from the smallest thing that 
has an individual existence, to the largest tree, all 
are constituted according to fixed laws ; — that the 
life, growth, health, and every thing belonging to the 
nature and properties and powers of the vegetable, 
are governed bjr the permanent laws which the Cre- 
ator has established and continually sustains, — the 
truth of what we affirm will still be unhesitatingly 
allowed. And finally, if ascending in the scale of 
creation, we advance to the animal kingdom, and 
assert that God has created every animal, and estab- 
lished all its properties and powers upon fixed prin- 
ciples ; that even in the formation of the bones and 

muscles and nerves, and all the organs of the human 
body, with their mysterious and wonderful endow, 
ments— law and order and adaptation to special pur. 
poses and ends, prevail and govern every thing, — 
even here the truth of what we predicate will be ad- 

14. Thus, from the nice adjustments and balanc- 
ing of revolving worlds, to the structure and operation 
of the organs of the smallest insect, and the simplest 
vegetable, and even to the arrangement of the par- 
ticles of matter in the formation of minerals ; and all 
the combinations of the elements of nature by which 
the various forms and properties of matter are pro- 
duced ; — throughout the whole immensity of created 
things — mankind will readily admit that an intelli- 
gent and wise and benevolent Creator has established 
laws ; and that by virtue of the laws which he has 
established and continues to sustain, the forms and 
properties and powers of all material things are what 
they are. All, except the atheist, will frankly ac- 
knowledge that it is befitting a God of infinite intel- 
ligence and wisdom and goodness, that all the works 
of his hands should be established in order and har- 
monious system, and governed by precise and un- 
changring laws. And even he who denies the existence 
of a God, is forward to confess that eternal and un- 
varying laws reign in and over every thing ; and that, 
by the energy of those laws of nature^ all the forms 
and conditions of nature are produced, and are pre. 
served. Vet, strange to tell ! when all these ac- 
knowledgments are made concerning the laws which 
govern the material universe and all material forms, 
if we turn to the higher order of God's works, in which 
he has associated with organised matter, in human 
nature, organic vitality and animal* consciousness, • 
and sensibility and voluntary motion, and intellectual 
and moral .powers, and affirm that human life and 
health, and thought and feeling are governed bylaws 
as precise and fixed and immutable as those which 
hold the planets in their orbits, and cause all portions 
of each globe to press towards its centre, and point 
the trembling needle to the pole, and govern all the 
molecular aggregations and combinations and ar- 
rangements of matter in the inorganic and organic 
world, mankind will, almost universally, without a 
pause for thought, deny the truth of the affirmation, 
and contend that human life and health and disease 
are matters of entire uncertainty, governed by no 
laws, and subject only to the arbitrary control of 
God, or the blind necessity of fate, or the utter con. 
tingency of accident. They do not believe that there 
are any fixed laws of life, by the proper observance 
of which, man can, with any certainty, avoid disease 
and preserve health, and prolong his bodily existence ; 
and they are confident that the experience of the hu- 
man family in all ages has fully and conclusively 
demon&tratied the correctness of their views. 

15. In the same circumstances and habits of life, 
they affirm, one enjoys good health, and another is 
frequently or continually diseased ; one dies early, 
and another reaches an advanced period of life ; while 
people of x'ery different, and even opposite circum- 
stances and habits,, experience the same uncertain, 
ties and share tho same fate ; some enjoying health, 
and others being afflicted with disease; some finding ' 
an early grave, and some attaining to old age ; and in 
all circumstances and habits, the vigorous and robust 
often die suddenly in the opening of manhood or the 
very prime of life, while the feeble and the sickly fre- 
quently drag out a protracted and miserable existence. 
Survey, say they, the extended map of the earth, 
and we find the inhabitants of one portion feeding on 
the putrescent carcasses of dead animals, others on 
noisome vermin and reptiles, others on a mixture of 
animal and vegetable substance, others on vegetables 
exclusively, and others allaying their hunger, and to 
some extent supplying the alhnentary wants of their 


nature, with unotuout earths. Some indulging freely 
in ihe vae of tobacco, others in opium, others in ar. 
rack, others in rum, or some of the numerous forms 
of alcoholic liquor; and yet, with these differences 
of dietetic habits, and all the difference of climate 
from the equator tb the poles, we find, it is said, 
among all the different tribes and portions of the hu- 
man fiunily, about an equal share of health and dis- 
ease, premature death and extended life. And, while 
the Esquimaux feasts with gustatory satisfaction and 
cielight on his carrion flesh, and derives from it the 
most healthful and invigorating sustenance to his body, 
the Hindoo, with equal gustatory enjoyment and 
health, makes his repast on his dish of rice ; yet, if 
the diet of these two be exchanged, and the Bsqui* 
maux be fed on the rice and the Hindoo on the flesh, 
both will be disgusted and both will be made sick. 

16. Thus, we are told, it is completely demonstrated 
by the experience of all nations and all ages, that 
human life and health and disease are matters 
either of absolute fatality or perfect contingiBnoy ; and 
that, in regard to them, there is no fixed philosophi- 
cal relation between cause and effect; and there- 
fore, the life, health, disease, and diet of man, can. 
not be governed by fixed laws, nor made matters of 
systematic science. 

17« This reasoning, at first view, appears forcible 
and conclusive ; but when thoroughlv examined, it 
proves to be entirely fallacious : and the more deeply 
and extensively we push our investigations on this 
subject, the more ^Uy are we convinced that human 
life, health, disease, diet, a&d general regimen, are 
matters of as pure and nearly as exact science as ma* 
thematics. Indeed, human physiology, in the full 
sense of the term, is far the most profound and im- 
portant science that has ever occupied the attention of 
man ; and in order to the most perfect understanding 
of it, a knowledge of all other sciences is requisite. 
In fact, it may almost be said that this science con- 
sists of the sum of all other sciences systematized 
into one ; and the only reasons why the notions of 
mankind are so vague and erroneous* on this subject 
are that they never study' it as a science ; and moMt 
or all of their opinions are the results of feeling^ or 
what they miscall experience, rather than of deep 
reasoning and philosophical investigation. Nor is it 
surprising that it should be so, when the nature of 
man as a rational animal, and the circumstances in 
which he is placed, and the influences which act on his 
natural and moral susceptibilities, are accurately 

18. In the rude state of nature, the wants of man 
are few and simple. If hungry, he plucks the fruit 
from the bough of the tree, or gathers some nutritious 
substance from the earth, and satisfies his want. If 
thirstv, he stoops to the clear fountain or stream, or 
with bis hand, or with a folded vegetable leaf, lifts 
the pure beverage of nature to his lips, and answers the 
instinctive demand; or perhaps more naturally, he 
satisfies this want with the juices of succulent fruits. 
if. cold, he wraps his body in the skins of beasts ; if 
oppressed with heat, he retires to the cool shade of 
trees. When the sun sinks below the western hori. 
son, and the curtain of night gathers over him, he 
throws himself upon the bosom of the earth, or on 
some rudelv prepared couch, and sleeps till the re- 
turning lignt rouses him, friesh and vigorous, from his 
slumb^s : or if he inhabits a portion of the globe 
where darkness prevails for months, he sleeps and 
wakes according to the instinctive demands of his 
nature. The apparent revolutions of the sun, the 
waxing and the waning of the moon, and the changes 
of the seasons, constitute his only chronometer. 

19. In all this, it is manifest, that the rational powert 
of man are little employed in investigating the adapt- 
ation of his diet and habits to the laws of organic 
vitaHty* Possessed of the instincts common to all 

animals, he feels his wants, and by the feeUng, is 
prompted like other animals to satisfy them ; and, in 
doing this, he is governed by those instinctive powers 
of smell and taste, which enable him with utmost 
accuracy to discriminate between esculent and poison- 
ous substances. And, if reasoning po^rs of a higher 
order than those which are exercised by other animals 
are employed by him, it is in devising the means by 
which his supplies are procured, rather than in ascer- 
taining the fitness of those supplies to the real con- 
stitutional wants of his nature. 

20. As man gradually becomes removed from the 
simplest state of nature, by the artificial habits and 
circumstances of society, he finds it first convenient 
and then necessary to possess those rude utensils — the 
earliest specimens of human art — with which he pre- 
pares his food, and dtps his water from the brook, and 
fits his clothing for his body. No sooner are these 
things considered necessary, then the supply of them 
becomes of nearly, as much importance as food and 
drink and clothing. This, in time, leads individuals 
to devote themselves wholly to the manufacture of 
such articles as the wants of society demand : and 
this leads to an increase of skill and knowledge in the 
manufacturing art, and a consequent improvement of 
the things manufactured : and this reacts upon soci- 
ety, and accelerates its progress towards what are 
called the refinements of civic life : and this, again, 
while it continually multiplies the artificial wants of 
man, increases the necessity for the supply of those 
wants : and the final result is, that the artificial 
wants of man become so numerous and so imperious, 
that a large portion of the time and powers of every 
member of society are employed in supplying them : 
and, in the progress of the development of this state 
of things, the several arts and sciences of civic life 
are originated and matured. 

21. Thus, from the simple instinct of thirst, or na- 
tural want of water, has grown the invention or dis- 
covery and manufacture of the numerous beverages 
or kinds of liquor drank by man, and of the boundless 
variety of cups, glasses and vessels of every descrip- 
tion, employed in containing water, tea, coffee, wine, 
and all other kinds of alcoholic and other liquors used 
as human drink. And out of the simple instinct of 
hunger, has grown all the devices and arts concerned 
in producing, procuring and preparing food, and the 
invention and manufacture of all culinary utensils ; 
and all the dishes, tables and other articles used in 
cooking, holding and serving up the aliments of man. 
And out of the want of clothing, which was at first 
supplied by a light tissue of leaves or by the skins of 
beasts, has grown the manufacture of the intermin- 
able variety of articles made of wool, flax, silk, cot- 
ton, fur, etc., etc. 

32. In the progress of these arts and operations, 
one want has created another; and caused a continual 
demand for the closest and most constant application 
of the mental powers of man to the investigation of 
the physical, mechanical and chemical properties of 
things, and with reference to forces, motions, numbers, 
quantities, time, distance, etc., etc., till mathematics, 
astronomy, chemistry, and all other human sciences 
have been slowly developed and matured, and become 
themselves some of -the most important wants of 

23. But it is obvious that, in this general progress 
of things, by which new wants are continually and 
rapidly generated and multiplied, there is little to 
lead the mind of man to study the laws of human life, 
or to examine the dietetic and other habits of civic 
life with reference to health and disease. 

24. The artizan who manufactured the first rude 
cup or goblet, probably never gave a thought to the 
question whether water or some other liquid is best 
adapted to the natural wants of man ; and since him, 
the thousands who have been employed in the same 



Une of art, have seldom, if ever, been led by their oc- 
cupation to inquire whether wine, tea, coffee and other 
alcoholic and narcotic beverages are ada{)ted to the 
real wants of the human body, or are consistent with 
the laws of life and health. On the contrary, the 
very employmAit and circumstances of every artizan, 
require the constant application of his mental powers 
to the principles and operations of his art, in order 
to his immediate success as an artizan, and to his ul- 
timate pecuniary success as a member of society. The 
wants of civic life are so numerous, and constitute so 
important a part of the very texture of social and 
domestic life, that every man finds nearly his whole 
time and attention taken up in supplying them. 
■ 25. It is true, that disease multiplies in society in 
proportion as man removes from a pure state of na- 
ture, and becomes more and more an artificial being 
in his habits and circumstances :* and this leads to 
the study of the healing art, and ultimately to the 
itudy of anatomy and physiology. But, even here, 
the general tendency of things is far less favorable to 
the accurate and profound study of the science of 
human life, than is generally supposed. 

26. Disease always precedes the physician ; and the 
sick are only concerned to know how they can obtain 
the most speedy relief from their sufferings. The ques- 
tion with them, and with their friends, is not, how 
they came by their sickness, or by what violations of 
the laws of life it has been induced, but by what re- 
medies they can remove the disease and restore health. 

27. The domestic therapeutics of the earliest stages 
of society is generally extremely simple ; and is per- 
haps governed at first, by the morbid cravings of the 
patient, by accident, and finally, by experience. If 
by any means the disease is removed, the remedies and 
measures employed are carefully remembered, and 
used again, when similar cases occur; and in this 
manner, every tribe, and almost every family soon 
acquire their system of pharmacy and their theory 
and practice of medicine. 

28. As society advances and diseases become more 
numerous and frequent, it follows as a necessary re- 
sult, from the consequent order of things, that indi- 
viduals become devoted to the study of remedies, and 
to the care of the sick ; and thus, physicians origi- 
nate. The office is, perhaps, more frequently at 
first, confined to the priesthood, who employ with 
their simple remedies, an abundance of superstitious 
juggling, and incantation and exorcism. In time, 
however, some master spirit like Hippocrates, rises 
np, and digests the chaos of crude elements, into 
something like order and system. But it is obvious 
that, from the first rude origin of these elements to 
their systematic arrangement, every thing is done 
simply with a view to cure the disease, and without 
any regard to its cause : and, indeed, the disease it- 
self is generally considered as the direct and vindic- 
tive infliction of some benevolent or malevolent su- 
pernatural being or beings ; and therefore, in all the 
progress of the healing art thus far, not a step is taken 
towards investigating the laws of life and health, 
and the philosophy of disease. 

29. Nor, after medicine had received a more sys- 
tematic form from the plastic hand of Hippocrates, 
did it lead its votaries to those researches which 
were most essential to its success, and which its great 
importance to society demanded ; but like religion 
and everything else in the hands of man, it became 
blended with the grossest superstitions, errors and 
absurdities. Hence, from the earliest traditions of 

* By * a pure state of nature,' let it ])e understood, once for all, 
that I never meau the savage state ; for I consider the savage 
state, in manjr respects, very far ft-om the truly natural state, of 
man, and themore, I distinguish between the rude state of nature 
(18) and the pure state of nature. By the latter, I always mean 
that state in which the condition, circumstances and habits of man 
are in strict and tall accordance with the constitutional laws of 
his nature. 

Eg^pt, until comparatively modern times, the his- 
tory of medicine, with very limited exceptions, is a 
tissue of ignorance and foUy, error and absurdity ; 
and only serves to demonstrate the absence of that 
knowledge upon which alone an enlightened and 
successful system of medicine clfch be founded ; and 
to show to what extent a noble, and I might perhaps 
with propriety say divine art, can be degraded, and 
perverted from its high capabilities of good, to almost 
unmixed evil, by the gross ignorance and sensuality 
and superstition and cupidity of man. 

30. In ascertaining and defining the symptoms of 
disease, with reference to the application of remedies, 
some of the ancients certainly did much for the heal- 
ing art; and they undoubtedly made considerable 
attainments in the knowledge of anatomy and sur- 
gery. But we ought to know that all this may be 
done, with almost entire ignorance of the laws of life, 
and the true philosophy of disease. Still, however, 
it must be admitted that, with all the disadvantages 
under which he labored in regard to physiological 
knowledge, the therapeutic views of Hippocrates were 
such as justly entitled him to be called ' the Father of 

31. In modern times, anatomy and surgery have 
been carried perhaps nearly to the top of perfection ; 
and very great attainments have been made in physi- 
ology. The science of human life has been studied 
with intense interest and remarkable success : but 
this has been confined to the devoted few ; while, even 
in our own day, and in the medical profession itself, 
the general and powerful tendency of things, is ad- 
verse to the increase and diffusion of scientific know- 
ledge, in regard to human life, health and disease. 

32. Intent as all men are on present enjoyment, 
they are little inclined to practise present self-denial 
for the sake of a future good, which they consider in 
any possible degree contingent ; and will only consent 
to bear the cross when compelled by necessity, or 
when they find it the only means of shunning immi- 
nent destruction, or of escaping from intolerable 
evils. Hence, so long as mankind are favored with 
even a moderate degree of health, they rush into the 
eagerly desired excitements of their various pursuits 
and pleasures and indulgences : and nothing seems to 
them more visionary and ridiculous, than precepts 
and regulations and admonitions concerning the pre- 
servation of health. While they possess health, they 
will not believe that they are in any danger of losing 
it ; or if they are, nothing in their habits or practices 
can have any effect, either in destroying or preserving 
it : nor can they be convinced of the universal delu- 
sion that, if they enjoy health, they have within 
themselves the constant demonstration that their 
habits and practices are conformable to the laws of 
health, at least in their own constitutions. . They 
will not, therefore, consent to be benefited, contrarily 
to what they regard as necessary to their present en- 
joyment, either by the experience or by the learning 

33. The consequence is — as a general fact — that, 
while in health, mankind prodigally waste the re- 
sources of their constitution, as if the energies of life 
were inexhaustible ; and when, by the violence or by 
the continuance of their excesses, they have brought 
on acute or cbronic disease, which interrupts their 
pursuits and destroys their comforts, they fly to the 
physician, not to learn from him by what violation of 
what laws of life and health they have drawn the evil 
upon themselves, and by what means they can in 
future avoid the same and similar difficulties; but, 
considering themselves as unfortunate beings, visited 
with afflictions which they have in no manner been 
concerned in causing, they require the exercise of the 
physician's skill in the application of remedies, by 
which their sufferings may be alleviated and their 
disease removed. And in doing this, the more the 



practice of the physician conforms to the appetites of 
the patient, the greater is his popularity, and the more 
cheerfully and generously is he rewarded. 

34. Every thing, therefore, in the structure and 
operations of society, tends to confine the practising 
physician to the department of therapeutics, and make 
nim a mere curer of disease ; and the consequence is 
that, excepting the few who are particularly favored 
by their situation as public teachers, the medical fra- 
ternity, even of the present day, have little induce- 
ment, or opportunity, to apply themselves to the study 
of the science of human life, with that devotedness 
and zeal and perseverance, which the profoundness 
and intricacy of the subject require ; while, on the 
other hand, almost every thing by which men can be 
corrupted, is continually presented, to induce them to 
become the mere panders of human ignorance, and 
depravity, and lust: and if they do not sink their 
noble profession to the level of the vilest empyricism, 
it is owing to their own moral sensibility, and philan- 
thropy, and love of virtue, and magnanimity, rather 
than to the discriminating encouragement which they 
receive from society, to pursue an elevated, scientific, 
professional career. 

35. Thus, we see that both the natural and acquired 
appetites, propensities, and habits of man, and all the 
dircumstances of life which act on his natural and 
moral sensibilities, concur to divert his attention from 
the study of the science of human life, and fix it on 
present self-enjoyment, and on the pursuit of the 
means of supplying his natural and artificial wants. 
And hence, he is left to feel his way to, or gather 
from what he calls experience, most or all the con. 
elusions which he embraces, in regard to the laws of 
life, health, and disease. 

36. This source of knowledge is as utterly fallacious 
as it is delusively specious : and the more deeply and 
extensively mankind are betrayed by it, the more to- 
tally blinded do they become to its ^eachery, and the 
more zealously and confidently do they contend for 
its validity. 

37* Every one knows from his own feelings and 
experience precisely what kind of constitution he has ; 
and what agrees and what disagrees with it; — and 
every body knows exactly what agrees and what dis- 
agrees with his own stomach ; and is taught by his 
own experience, what is best for his constitution, and 
his health, and strength, and comfort. And surely, if 
a lady has the head-ache, she knows her own feelings 
better than any body else does ; and if she drinks a 
good strong cup of tea, and the pain leaves her head, 
nobody ought to be guilty of so gross an insult to her 
understanding, as to attempt to convince her that tea 
is a poison, and that her use of it is a principal cause 
of her head-ache; for she knows that she always feels 
better after drinking tea; and from fifteen or 'twenty 
years' experience, she knows that there is no better 
remedy for head-ache than a good strong cup of tea ; 
for she has been subject to the head-ache for nearly 
twenty years, and the frequency and violence of the 
turns have gradually increased upon her from the 
first, till she is now obliged to g^ve up all business, or 
pleasures, and take to hei^ bed for the whole day, 
whenever she has a turn, wnich is certainly as often 
as once a week, and sometimes more frequent ; and 
she has always found that tea is *' the sovereignest 
remedy in the world" for head-ache ! Who can reason 
against such facts as these ? or have the temerity to 
advance a theory which contradicts the universal ex- 
perience of the human race ? It must be confessed 
that the enterprise is an arduous and a daring one ; 
and is cheered by no encouraging prospect, except the 
possibility that mankind can be undeceived in regard 
to the validity of their feelings and their experience, 
as rules of life. 

. 88. I do not, however, wish to convince my fellow 
creatures that they have no feelings ; nor that they 

do not know when, and how much they feel : bat I 
wish to convince them that the kind and degree of 
their feelings, by no means teach them what causes 
it, nor the principles upon which its existence depends. 
I am willing to concede to the lady, that she knows 
best how her own head-ache feeU; and that she 
knows it is relieved by a cup of tea. But does she 
know either the remote or immediate cause of her 
head-ache } Does she know the vital properties and 
powers and functional relations of the organs of her 
body ? and does she accurately understand the healthy 
and the diseased affections and svmpathies of those 
organs ? Does she know the qualities of the tea in 
relation to the vital properties and functional powers 
of her system ? Does she know the direct and the 
ultimate effects of the tea on her system ? How it 
produces the pleasurable feelings, how it removes the 
pain of her head ? And does she know whether the 
very effects of the tea, by which the paroxysms of her 
head-ache are relieved, are not the principal source of 
her head-ache, and the main cause of the frequency 
and violence of the paroxysms ? If not, what are 
her feeling and experience worth, to herself or others, 
as rules of Ufe, by which she, or any one can judge of 
the fitness of her habits, to the laws of life and health ? 
I answer, not a farthing ! Nay, indeed ! they are 
worse than nothing ! mere delusions by which we are 
decoyed from step to step along the specious lab|rr- 
inths of sensuality and suffering. And such, with 
rarely an individual exception, is the universal expe- 
rience of mankind ! I acknowledge that they feel ; 
and that they know whether their feelings are pleasur- 
able or painful. But do they know physiologically 
h(tw or why they feel ; and understand the relation of 
their feelings to the powers and laws of vitality ; and 
to the condition and functions of the living organs ? 
I acknowledge that, by virtue of a vi^rous constitu- 
tion, many may live years, and some even to what 
we call old age, in the enjoyment of ordinary health, 
in spite of habitual violations of the laws of life and 
health. But does this constitute an experience which 
proves the correctness of their habits ? or at least, 
that those habits are not unfavorable to life and 
health, in certain constitutions ? Most evidently it 
does not ! 

39. It has been justly observed by a distinguished 
philosopher, that ' men in their inductive reasonings 
deceive themselves continually, and think that they 
are reasoning from facts and experience, when, in re- 
ality, they are only reasoning from a mixture of 
truth and falsehood. The only end answered by facts 
so incorrectly apprehended, is that of making error 
more incorrigible. Nothing, indeed, is so hostile 
to the interests of truth, as facts incorrectly ob- 
served.'* And on no subject are men so liable to 
misapprehend facts, and to mistake the relation be- 
tween cause and effect, as on that of human life, 
health and disease. Without the most profound phy- 
siological and pathological knowledge and discrimina- 
tion, it is not possible for them to avoid self-de^ 
ception. They constantly mistake the causes^ of their 
feelings, and misunderstand the physiological and 
pathological character of the feelings themselves. And, 
judging of the qualities of things by the feelings which 
they produce, and without considering that even the 
most baneful substances may be made the causes of 
pleasurable stimulation to depraved organs, they in- 
evitably confound good and evil, their facts become 
falsehoods, their inductions erroneous, and their ex- 
perience a tissue of error and absurdity, which serves 
only to mislead and to betray them. 

40. Nothing is more certain, therefore, than that 
the only way by which mankind can attain to correct 
notions concerning human life, health, disease, re- 
gimen, etc., is to apply their intellectual powers assid- 

* Playfur's AiutlyBis of Bacon's Novum Organnm. 



uou^ly to the study of the subject as a science ; and 
thiS' will lead theni| not as mere animals possessed of 
sensibility and consciousness, and the voluntary power 
of sensual indulgence, but as rational beings, over a 
most extensiji^e and interesting field of research and 

4:1« Could we seize upon vitality itself, and ascertain 
its essence, we might, perhaps, be able to reason from 
its iotirinsic properties and powers, to all conclusions 
necessary for our use, with a more limited extent of 
argument, and much less help from other sciences 
than we now find requisite. But we know nothing of 
the essence of life, and therefore we can only know 
its peculiar properties, and powers, and laws, by ac- 
curately ascertaining the character of its manifesta- 
tions and effects in relation to the ordinary laws and 
pr<^ertie8 of inorganic matter. 

42. We perceive, therefore, that the science of Hu- 
man Nature is most comprehensive as well as com- 
plicated and. profound : that it extends, not only over 
the iwhole man, embracing all his moral, intellectual, 
animal and organic properties, and reaching even to 
the vital forces and afiinities, from the action of which 
result the several arrangements, structures, tissues 
and organs of the body, but, in order to come at the 
truth on all these points, and ascertain how far the 
matter of the living body is subject to the common 
physical laws of the organic world, how far and in 
what manner the living body resists and overcomee 
those laws, and to what extent the vital economv is 
affected, and life modified by the presence of chemical 
agents, the force of chemical affinities, and the power 
of physical laws, it necessarily goes still farther, and 
investigates the properties and laws common to all 
matter ; and endeavors, in its analytical progress, to 
arrive as nearly as possible at the primordial form 
and essential nature of matter itself; and thus pre- 
pares the way to ascertain the differences and dis- 
tinctions between inorganic and organic matter, and 
to find out the properties and laws petniliar to all or- 
ganized matter, or all living vegetable and animal 
bodies ; and the differences and distinctions between 
vegetable and animal bodies, and the properties and 
laws peculiar to the latter; and in this way, finally 
brings us to the study of the particular anatomy and 
physiology and psychology of man. 

43. The subject is immense ! yet it is, in all its de- 
tails, replete with interest to every human being. 
M|in. finds himself upon the theatre of life, full of 
susceptibilities, surrounded by innumerable influences, 
and acted on at every point ; and he is continually 
conscious, not only of his existence and the action of 
surrounding influences, but of an unceasing desire 
fof happiness. Has Ood implanted this desire as a 
fundamental principle of action in our nature, merely 
to tantalize us in the vain pursuit of what has no re- 
ality ? or is the desire itself a living proof that our 
benevolent Creator has fitted us for happiness, not 
only in a future state, but here—in soul and body ? 
and adapted every thing within us and around us, to 
answer this desire, in the fulfilment of those laws of 
life and health and happiness which he, in wisdom 
and in goodness, has established in the constitutional 
nature of things } 

44. Surely our heavenly Father cannot but prefer 
our happiness at every instant of our lives ; and if we 
are not happy it cannot be because he has not endow, 
ed us with the capability of being so, and adapted 
earth and all terrestrial things to all that he has 
made us capable of being. 

45. Our disquietudes, and diseases, and untimely 
death, must therefore spring, not from the fulfilment, 
but from the infraction of the laws of God ; and it 
becomes us humbly, yet diligently, to endeavor to as- 
certain those laws, and to obey them and be happy ; 
and thus fulfil the benevolent purposes of God, and 
glorify him in our spiriU and our bodies, which are hit. 

46. It is impossible to attain to a full understanding 
of these things without a determined and persevering 
application of the mind ; and for the sake of know- 
ledge so important, we must be willing to submit 
even to the drudgery of that application which at 
first is made only with the hope of being rewarded 
when the task is mastered, and hidden things aro 
brought to light by penetrating diligence. 


The variety of material fomu— Their origin— apparent difference, 
between organic and inorganic matter— Great variety of oi^anic 
forms— Svatematised into a few classes— Order and design in 
every thing — Organic and inorganic bodies resolved to the 
same elements — All things in the material world resolved to a 
few simple substances — Wonderful powers of vital chemistry in 
vegetable and animal bodies — All kinds of aliment converted 
into the same organized substances — The various forms of mat- 
ter composed of minute primordial atoms, the same in organic 
and inorganic bodies — differently arranged— Intimate relations, 
between all material forms— What is matter! — Moses' account 
of the creation 1— St. Paul's explanation— A single element of 
matter— Opinions of Braconnot, Sir Humphrey Davy, Dr. 
Herschel, Dr. Amot, Sir J. F. W. Herschel, Dr. Prout, and 
others — Original formation of things — ^The ageney of an int^- 
Ifgent and oomipotent Creator necessary— The intrinsic pro- 
perties of matter could not produce the results of nature — No 
law nor property of matter Imown to be essential to it— We 
know no more of matter than of spirit— Original forms and 
primitive combinations of matters-Number of chemical ele- 
ments — Water, how formed— Rocks—Earth, etc. — The Neptu- 
nian and Plutonian theories of Geology — Natural elements few, 
or one— Essentially the same matter in all forms— Inorganic 
affinities could not produce organised bodies and life— Opposi- 
tion of organic and inorganic affinities — Life not the result of 
organized matter, but the contrary— The inorganic world left to 
itself must have remained eternally so, without a blade of 
grass — The necessity for an intelligent and omnipotent Creator. 

47. If, in our imagination, we assume some elevated 
stand, and contemplate the surface of our globe, we 
behold mountains and valleys, hills and plains, bound- 
ed by oceans, and intersected by rivers and streams, 
and clothed with vegetation, and swarming with a 
vast variety of animus. Pleased with the interesting 
view, we are naturally led to inquire, whence all this 
beautiful variety of things ? l)o they constitute but 
a part of an eternal succession of material and living 
forms ? Or is this globe with < all that inhabits it,' 
but the wreck or fragment of something more mag- 
nificent and vast ? Or are these things the blind 
result of chance ? Or, far retired behind these 
mighty works, is there a mightier Architect, whose 
power and wisdom and design, for some great purpose 
of benevolence, created and constructed every tUng? 
But in vain we question nature in thif general 
manner ! No distinct and definite answer is aflPorded 
us. If, with the spirit of philosophioal inquiry, we 
descend from our elevated situation and general view, 
and approach to a nearer and more intimate inspec- 
tion of the several parts of the great scene before us, 
we behold the mineral and vegetable and animal 
kingdoms displayed around us in splendor and luxu- 
riance and beauty and enjoyment. Profusion and 
variety and disorder seem, at first glance, to prevail 
throughout the whole. Between inorganic and ve- 
getable and animal matter, there appears to be not 
only a distinction of forms, but an essential difiTerence 
even in the ultimate elements. 

48. Turning our more particular attention to the 
organic world, it appears, at first view, as if nature 
had spontaneously thrown out an interminable vari- 
ety of forms, without regard to order or design. 
But when we come to a more close and careful exam- 
ination, we discover that the most perfect order per- 
vades the whole, and that interminable as the variety 
at first appeared, all may be arranged into a few 
classes, each of which embraces but a limited number 
of species ; and the more rigorously we scrutinize the 
individual forms of things, in order to ascertain their 
peculiar iitructure and properties, and constitutional 



prinoiples and laws, the more dearly we perceive 
order and design in every part, and perfect fitness 
and harmony mgning through all. At each advanc 
ing step, we discern more and more distinctly on 
every part, the deep and indelible hand*writing of 
Creative Intelligence, and Design and Goodness ! In 
every animal — in every vegetable form, God has 
stereotyped a living alphabet, by which we can Spell 
out his power and wisdom and benevolence ! 

49. Not satisfied with these discoveries, we begin 
more boldly to demand of Nature the disclosure of 
her secret things, and in the crucible, and by other 
modes of analysis, compel her to divulge her most 
hidden principles. All living bodies, and the atmos- 
phere and ocean, and the earth, even to her inmost 
entrails, are exnlored. The solid forms of matter 
melt beneath the fiery inquisition ! The earths 
shrink into metaJlic bases ! and these again, if still 
pursued with sufficient intensity of heat, vanish into 
thin vapor — apparent nothingness! And we are 
astonished to perceive that, essentially different as 
we suppose the animal and vegetable and inorganic 
tubstances which we subjected to our analytical 
ordeal, yet the results exhibited the same ultimate 
elements in all, or only differing in their proximate 

50. Bnconraged by our success, we eagerly urge 
onward our experiments, till we seem about to step 
upon, the threshold of ultimate analysis ; and arrive 
at the full conviction that every fluid and every solid 
substance in the world — even the hardest minerals, 
may, with sufficient heat, be converted into thin air 
or.gas ! and we learn that all things composing and 
inhabiting this globe of and inorganic, 
may by chemical analysis even in the hands of man, 
be resolved into a few forms or substances, which in 
the present state of science we find convenient to call 

61. But the vital alchemy of the organic laboratory, 
leaves the chemist's crucible, and the more simple 
operations of inorganic nature, far behind in its en- 
ergy of analysis and in its creative aggregations and 
arrangements; and seems to possess the power not 
only of decomposing rinost, if not all of those sub- 
stances which are called elements, but also, of actu- 
ally transmuting them into each other. 
' 62. * The seeds of various plants,* says a distin- 
guished chemist, ' may be placed in pure sea-sand, or 
even leaden shot, and nourished with nothing but 
pure distilled - water, and the common atmosphere, 
and the sun*s light and heat, and the seeds will sprout 
and the plants grow and thrive, and attain to matu- 
rity, elaborating for themselves, out of the distilled 
water and the atmosphere, all their own nutriment, 
and properly arranging and composing the several 
vegetable structures and substances, and producing 
the several, vegetable properties. And if this vege- 
table matter thus produced, be carefully preserved 
and accurately analyzed, the various earths, the alka- 
lies, acids, metals, carbon, sulphur, phosphorus, nitro- 
gen, etc., may be obtained the same, or nearly the 
same as if the plants had grown in their natural soil.* 

63, *It is well known,* says Dr. Turner, in his 
Elements of Chemistry, 'that many plants grow 
when merely suspended in the air. In the hot-houses 
of the botanical garden of Edinburgh, for example, 
there are two plants, species of the fig tree, the 
Pieus atutralit and the Ficut elastica, the latter of 
which, as Dr. Graham informs me, has been sus- 
pehded for four, and the former for nearly ten years, 
duiing which time they have continued to send out 
shoots and leaves.* 

64. * The Aerial Epidendrum, a beautiful plant of 
Java and of the East Indies beyond the Ganges,' 
says an eminent physiologist, ' has no roots nor any 
apparent organs of nutrition, but lives alone on air 
and the T»por of the atmosphere. It is said to be no 

uncommon thing for the inhabitants to pluck it up oil 
account of the degance of its leaves and the beauty 
of its flower^ and the exquisite odor which it diffuses, 
and to suspend it by a sUken cord from the ceiling of 
their rooms, where from year to year, it continues to 
put forth new leaves, new blossoms and new fra- 
grance, excited to new life and action only by light 
and heat and the surrounding atmosphere.* 

55. Here then, the atmosphere, with the assistance 
of light and heat, is converted by the vital forces of 
the vegetable organic economy, into fluid and solid 
vegetable substance, color and fragrance ; and if this 
vegetable matter be carefully analyzed, it will afford 
many of those substances, or forms of matter, which 
chemists now call elements, and which no analysis 
that they are capable of making, has, as yet, been 
able to detect in the substances by which the plants 
were nourished. 

56. If, therefore, earths and alkalies and acids and 
metals and sulphur and phosphorus, and other equally 
simple substances, may be elaborated by the vital 
power of the vegetable economy from the oxygen. and 
nitrogen and hydrogen and carbon of the common 
atmosphere, with what propriety can they be con- 
sidered elements, or primordial forms of matter ? 

57. ' The cerealia produce pure silex or flint, though 
not a particle of it is to be found in the soil in which 
they grew, nor in the fluid by which they are nou- 
rished. Plant in the same soil, the sugar cane, the 
aloe and the nightshade ; water them with distilled 
water, and let them grow side by side, warmed and 
invigorated by the same heat and light and atmos- 
phere, and the juice of the one will afford nutritious 
sugar ; of another, the medicinal, intensely bitter 
aloes ; and of the third, a substance with but little 
taste, but a deadly poison. From the sap of the peach 
tree, are produced the woody structure, the verdant 
foliage, the blossom with its beautiful tints and de> 
lightful fragrance, and the delicious fruit ; while in 
the leaves and kernel is formed a pungent bitter, and 
the prussic acid, which, in its concentrated state, is 
one of the most deadly poisons known. The may- 
apple or mandrake, which grows wild in our woods, 
bears a fruit which is esculent and fine flavored when 
ripe, while its root is a purgative of about the same 
power as jalap, and the leaf is actively poisonous.' 

58. * Thus, from the common sap,* says Dr. Good, 
t which may itself be elaborated entirely from pure 
water and the atmosphere, with the help of light and 
heat, are secreted a variety of substances of different, 
and frequently of opposite powers and qualities : sub- 
stances nutritive, medical, or destructive ^ and often 
in the same individual plant, some of its organs se- 
crete a wholesome aliment, while others secrete a 
deadly poison.* 

59. Nor is the vital economy of the animal system 
less wonderful in its analytical and synthetic powers. 
From all the varieties of aliment with which it is sup- 
plied, whatever may be the chemical properties of the 
food, it constantly and with utmost integrity, during^ 
health, produces chyme, chyle and blood, of very nearly 
the same chemical character : and whatever may be the 
kind of nourishment received into the stomach, in a 
healthy state of the system, the blood elaborated from 
it regularly affords the appropriate supply of mate- 
rials to every structure and substance of the body, 
whether the particular properties or substances de- 
rived from an analysis of the several structures be 
found in the aliment or not. 

60. Neither in the chyle nor in the blood is any 
gelatine ever found, and yet the most extensive struc- 
ture of the whole body is principally composed of this 
substance ; and the quantity of carbon eliminated by 
the human body, seems very greatly to exceed the 
quantity received into it in any appreciable manner. 

61. Moreover, the vital economy seems to possess 
the power, of varying the quantity of partioular qnal- 




ities and substances produced by it, accordin|^ to the 
condition and demands of the system, periodically 
supplying from the common and ordinary current of 
blood, without any known variation in the food from 
which it is elaborated, a ver^r large increase of appro- 
priate nourishment, for particular structures, and at 
the same time, regularly sustaining the general func- 
tion of nutrition^ in every part and substance of the 

62. Whatever may be the kind or quality of the 
food from which it is elaborated, the blood of man 
will always afford, by chemical analysis, a consider- 
able quantity of iron. Several other metals and other 
substances are also procured in the same manner, 
from the animal system, which it would be difficult, 
if not impossible, to account for in any other satis- 
factory way, than by admitting the power of the vital 
economy to produce, from a nearly homogeneous 
chyle, various substances which in chemistry are 
considered not only opposite in their qualities, but of 
essentially different elements. 

63. In the same animal, from the same vital cur- 
rent which nourishes the flesh, that would be perfectly 
safe and nutritious for human aliment, is secreted the 
most deadly poison. The flesh of the rattlesnake is 
eaten by many people, as a great luxury : and even 
its blood may be received into the human stomach, or 
put upon a fresh wound with perfect safety ; and yet, 
from the same blood, is secreted a poison, which if 
mingled With the blood of our systems, will, with 
almost irremediable certainty, prove fatal in a very 
short time. 

64. Besides these natural and ordinary operations 
of the vital economy of the animal svstem, it is no un. 
common thing for protracted irritations, and diseased 
action to produce results totally different from those 
of the normal or healthy and regular functions of the 
organs ; and the blood, which in the healthy condi- 
tion and action of the parts, regularly supplies ap- 
propriate nourishment for the soft solids, is made to 
yield the materials for the structure of bone : and 
thus, ossification has taken place in the heart and 
other important organs, to an extent which has often 
proved fatal to life. 

65. All the beautiful variety of things, therefore, 
which we, at first, supposed essentially different, may 
be resolved by the keen scrutiny of analvtical science, 
to a very few substances, which are called elements^ 
because they have hitherto withstood the utmost 
powers of analysis in the hands of man ; and yet, 
such have been the astonishing results of human in- 
vestigations, that men of high and wonderful attain- 
ments in science begin to tell us that 'it is scarcely 
possible to say what substances are not compound 
bodies :* and still, as we have seen, the nicer aldbemy 
of the organic laboratory, penetrates far beyond the 
reach of human science, and seems to have tne power 
to decompose and combine and generate with idmost 
a creative energy. And the sacred Scriptures afibm 
that ' the time shall come when all these things shall 
be disMohed, and the ehmenis shall melt with fervent 

66. If now we interrogate Nature in another mode, 
new revelations of her secret things astonish and 
delight us : and from her disclosures and her intima- 
tions, we are led to the conjecture, and feel ourselves 
urged to the conclusion, that the various forms of 
matter are composed of almost infinitely minute 
atoms (78, 79) ; and that these little molecules are 
precisely the same, whether in animal, vegetable, 
or inor^^anic structure ; precisely the same, whether 
composing the animated flesh <i man, the beautiful 
and fragrant flower, or delicious fruit of the vegetable, 
or thd hardest mineral, or the most subtile and elastic 
air : and that it is only. the different arrangements 
or aggregations of these atoms, that constitute the 
different material substances and qualities and forms. 

organic and inorganic. Nor is it probable that, in the 
various transformations of matter, which are con- 
tinually going on, the analysis that takes place in the 
processes of Nature, often approaches near to the 
primordial atoms ; but molecules composed of myriads 
of those atoms, may be the ultimate forms in most of 
the ordinary changes of composition and decomposi- 
tion in nature. 

67. Thus, of those forms of matter which in chem- 
istry are at present considered elements, different 
aggregations of the same molecules, make substances 
not oruy of entirely different natures, but of properties 
as different as those of aquafortis and the balmy air 
which we breathe ; of sugar and vinegar ; of charcoal 
and diamond. And thus again, by differently ar- 
ranging the same molecules of matter, red, orange, 
yellow, green, blue, and other colors and tints are 
produced ; and in like manner, are formed the most 
fragrant and most offensive odor ; and the different 
quiJities of sweet and sour and bitter, etc. And there 
are reasons for believing that light and heat, and elec- 
tricity and magnetism, insteaid of being essentially 
different substances, are but the results of particular 
aggregations or arrangements and conditions of the 
same primary atoms of matter. 

68. If these things be so, they reveal to us most 
intimate relations between all material forms and 
substances, which hitherto we have little thought 
of; and we learn from them our natural fellowship 
with earth and ocean and the atmosphere and every 
thing around us. 

69. What,' then, is matter ? and what was its pri- 
mordial form ? and what are its essential properties ? 

Moses instructs us that, < In the beginning God 
created the heaven and the earth !' And having 
made this general predication of his subject, he com- 
mences a brief history of the creation, in detail ; and 
declares that, previous to the creation of the earth, it 
was ^emptiness and nothing,'' or had no perceptible 
existence ; for euch is the radical and primitive sense 
of the Hebrew words in the original text ; and such 
is the sense which the apostle Paul, who was a learned 
Hebrew scholar, gives them, when speaking of the 
same subject, in his epistle to the Hebrews. * Through 
faith,' says he, ' we understand that the worlds were 
formed by the word of God ; so that the things which 
are seen were not made of things which do appear.' 
The writer of the book of Job and the prophet 
Isaiah also use the s^me Hebrew words in this sense. 

70. There is nothing in the Hebrew text, therefore, 
to justify the notion that our globe was formed out 
of a chaotic mass of matter, which might have been 
the wreck of some other planet, or of a comet, or 
fragment of the sun : but the true sense of the pas- 
sage is nothing more nor less than that before God 
created our globe, this material world of ours had no 
perceptible existence; it was ^emptiness and nothing.' 

71. The interesting question therefore still recurs : 
What is matter ? wluch we see displayed around us, 
in such multitudinous forms of ma^ificence and 
beauty and life and activity and sensibility and pas- 
sion and enjoyment ? 

72. From the many interesting facts and consider, 
ations which have now been presented, and a multi- 
tude of others which may be observed by the philoso- 
phic inquirer, on every hand, are we not urged to the 
conclusion that all these material forms and substan- 
ces and qualities and things, which now compose our 
palpable universe, are but the different modifications, 
or arrangements, of the same primordial atoms which 
constitute the single element or essence of all 
matter $ 

73. It is true that the demonstrations of human 
science have not yet arrived at this grand conclusion, 
and it is possible that they never will : but it is equally 
true that the glorious march of scientific discovery^ 
seems continually approaching toward this great 



point; and that every advancing step of analytical 
demonstration, -while it multiplies the proximate 
forms, draws apparently still nearer to the single ele- 
ment of matter. And it is an interesting fact, that 
many of the greatest minds which, in modem times, 
have heen devoted to the pursuits of natural science, 
appear almost simultaneously, as if inspired by Na- 
ture's great Spirit of Truth, to perceive indications of 
such a final consummation of analysis, and to inti- 
mate their conjectures of a single element; or, at 
most, a very few. 

74. ' Oxygen and hydrogen, with the assistance of 
solar light,' ^ays Braconnot, ' appear to be the only 
elementary substances employed in the constitution 
of the whole universe : and Nature, in h^ simple 
progress, works the most infinitely diversified effects, 
by the slightest modifications, in the means she em- 

75. ' A very few elementary bodies indeed,' says 
Sir Humphrey Davy, ^and which may themselves 
be only the different forms of some one and the same 
primary material^ constitute the sum total of our tan- 
gible universe of things.' And that distinguished 
philosopher, Dr. Herschel, has advanced the opinion, 
that Might is the source of all subbtances and the 
basis of all worlds.' 

76. ^Whether those substances which, in the 
present state of science, are considered elements,' 
says Dr. Arnot, ' are in truth originally and essen- 
tially different, or are only the one simple primordial 
matter^ modifieid by circumstances, as yet unknown to 
U8, we cannot at present positively determine.* 

77* In a truly able and exceedingly interesting pre- 
liminary discourse on the study of Natural Philosophy, 
by J. F. W. Herschel, Esq., the same important idea 
is fully advanced. ' Philosophical Chemistry.' says 
Mr. Herschel, ' no more aims at determining uie one 
essential element, out of which all matter is formed—ihe 
one ultimate principle of the universe, than astronomy 
at discovering the origin of tbe planetary movements, 
in the application of a determinate projectile force in 
a determinate direction ; or geology at ascending to 
the creation of the earth. There may be such an 
ELEMENT. Some singular relations which have been 
pointed out, in the atomic weights of bodies, seem to 
suggest to minds fond of speculation, that there is. 
But philosophical chemistry is content to wait for 
some strikinfif fact, which may either occur unexpect- 
edly, or be led to by the slow progress of enlarged 
views, to disclose to us its existence.' 

78. * The discoveries of modern chemistry have 
gone far to establish the truth of an opinion enter- 
tained by 8om6 of the ancients, that the universe con- 
sists of distinct, separate, indivisible atoms (66), or 
individual beings, so minute as to escape our senses, 
except where united by millions, and by those agg^re- 
gations making up bodies of the smallest visible biuk.' 

79. * What is proved concerning the atomic theory,* 
(66) says Mr. Whewell, in his admirable treatise on 
Astronomy and general Physics, 'is that chemical 
and other effects take place as if they were the aggre- 
gate of the effects of certain particles of elements, the 
proportions of which particles are fixed and definite.' 
And Dr. Prout, in his profoundly scientific treatise 
on Chemistry and Meteorology, says, ' by element is 
here meant a principle that is not made up of others, 
and which consequently possesses an absolute and in- 
dependent existence. Whether one or more such 
elements exists, is not now our object to inquire. 
The astonishing discoveries of modern chemistry, 
have shown that many of those substances, formerly 
considered as elements, are in fact compounds ; and, 
as the science of chemistry is still progressive, it is 
probable that with the enlargement of its boundaries, 
there will still be a further diminution of the number 
of those substances which are, as yet, held to be 
simple.' Indeed the general train of reasoning 

throughout the whole of this very learned and ex- 
ceedingly interesting treatise, embraces the supposi- 
tion of only one essential form of matter, 

80. If, therefore, any importance may justly be 
allowed to the opinions of those who are devoted to 
the pursuits of science, and who occupy eminent sta- 
tions in the scieiitific world, we are nere, by high 
authority, decidedly corroborated in the conclusion 
that the minute atoms of a single element constitute 
the primordial forms of matter, by the various 
combmations, arrangement and aggregations of 
which, all the diversified and interesting forms of 
things in our material world are produced. 

81. Having pursued our anf^ytical inquiry concern- 
ing the nature and cTriginal form of matter, through 
the various researches of human science, and the 
still more discriminating and wonderfi^ process of the 
organic vital economy, till we have arrived, with the 
support of demonstration, apparently near to a single 
ultimate principle, with many known truths and man- 
ifest analogies leading to, and justifying the hypothe- 
sis of a single essence, or original element ; it now 
becomes necessary for us to travel down the deeply 
interesting course of synthetical arrangement imd 
conformation, till we have again returned to^tt 
present existing forina aild conditions of things; in 
order that, by such inteitigations, we may as clearly 
and as fully as possible, ascertain the laws of consti- 
tution and relation appertaining to the various forms 
of matter and modes o£ being ; and particularly such 
as are connected with the existence, and affect the 
condition of the hnttian race. 

82. Here we ard met, however, at the very outset 
of our career, by the exceedingly important question : 
How could such various forms and qtialities of matter 
be produced from the atoms of a single element by 
the action of any intrinsic physical properties or 
powers ? This interesting interrogation brings us at 
once to the great point at issue between Materialists 
and Theists. And it must frankly be confessed that 
it is not easy to conceive of the possibility, that this 
present variety of material forms and modes of ex- 
istence, could have resulted from different aggrega- 
tions of the atoms of a single element, nor of fifty 
elements, by the exclusive action of any intrinsic 
affinities or properties of the elementary atoms, or 
forms of matter. 

^ 83. If there ever was a time, when the atoms of a 
single element or of fifty elements, lay in a quiescent 
state, with undisturbed affinities, then that state must 
have remained for ever, if some disturbing cause had 
not be^n introduced to excite the action of those af- 
finities, and produce combinations and new forms of 
matter : and when those affinities thus excited, had 
all exhausted their activity in such combinations, 
there they miist eternally have continued, bound by 
the laws of primitive conjugation, unless some new 
disturbing cause had again been introducied ; and so 
on, ad infinitum, matter would expend its chemicid 
activity, m every action that took place, and be to- 
tally destitute of the ability to take on new action 
and to change its form, without the agency of some 
new paramount disturbing cause, which should re- 
lax or overcome the law of its previous affinities, and 
superinduce another law of aggregation. 

84. To illustrate Jliis point, let us suppose that the 
two kinds of air called oxgen and hydrogen gases, are 
original elements of nature ; and that the atoms of 
which they are composed possess an intrinsic appe- 
tency or aMnity, which being excited to action by the 
combustion of the two gases together, in certain pro- 
portions, will result in the production of a third and 
entirely different form of matter which we call water. 
Suppose this room to be filled with those gases, in 
the proportion of two volumes of hydrogen to one of 
oxygen, and that they are completely secluded from the 
action and influence of all other causes : here they 



would retaain tow titer, withcmt entering into tbat 
•omMiMtioii which forms water, unless some new 
cause is introduced to bring their latent affinities into 
the naoelsary aoticm ; and if such a material cause 
were introduced, it must necessarily act upon the 
whole, and every atom of matter composing the two 
gates would enter into the formation of water ; and 
here the active power would be expended, and matter 
would eternally remain in the form of water ; unless 
again, some new cause were introduced, which would 
overeome those affinities, the action of which resulted 
in the formation of water, and bring into play other 
affinities, whose action would produce other forms of 
matter; and here again would be the end of action 
from any intrinsic affinity or power of matter. 

85. But perhaps it would be asserted that, with 
fifty elements, we can form a countless number of 
proximate elements, and, with these, by the various 
possible combinations, and in the various possible 
proportions with the original elements, we can pro- 
duce an infinite variety of substances and forms, 
which, acting upon each other as disturbing causes, 
can keep in eternal activity the affinities of matter, 
and thus cause an endless transformation of material 

86. This, it is acknowledged, is true to a consider, 
able- extent, if all that is assumed concerning the 
properties of elementary matter be admitted ; and 
yet, there is a limit far more circumscribed to the 
action of all these possible affinities and combinations 
and propositions, than is C(»mpatible with the reason- 
ing and hypotheses of atheistical philosophy ; a limit 
beyond which intrinsic atomic affinity and activity 
could not go ; and yet, beyond which matter has been 
carried to a wonderful extent by laws of arrangement 
which counteract and suspend its more primitive af. 
finities, and erect magnificent superstructures on the 
ruins of sill previous forms and qualities. It will be 
seen in the progress of our investigations, that there are 
forms and modes of material existence, resulting from 
the action of powers and qualities and affinities, 
which are so entirely different from, and in fact op- 
posite to, all that can be considered the more primitive 
atomic properties, that it is not possible they ever 
could have been, or ever can be produced by any in- 
trinsic appetency or power of matter, even though we 
admit the existence of a thousand elements. 

87. But, although modern chemistry has distribut- 
ed matter into morethan fifty elements or simple sub- 
stances, yet is it not evident from what has been ad- 
vanced on the present occasion, that the elements of 
nature must consist of a much smaller number ? and 
do there not appear to be many and strong reasons for 
believing that there is but a single original element, 
or essence of all matter ? How extremely subtil and 
refined and sublimated that material essence in itself 
may be, or what may be its distinction from, or prox- 
imity to, spiritual substance, it is not possible for us 
to form a clear conception, nor even for our imagina- 
tions to shadow forth an indistinct idea ! 

88. Moreover, it is an interesting and important 
truth, that there is not 'a single known property or 
law of matter of which human science can with cer- 
tainty affirm that it is essential to the nature of mat- 
ter. £ven gravitation, the most universal and all- 
pervading property or law of master known to man, 
may only appertain to certain forms and conditions of 
matter, and not be in any degree an intrinsic pro- 
perty of its essence. And' this is true of magnetism, 
and electricity, and molecular affinity, and every 
other known property. Indeed we know no more of 
the nature of matter, and of what are its essential 
properties, than we do of spirit. To some extent, we 
can appreciate its forms, and ascertain the properties 
connected with those forms, and the laws which 
govern their motions and changes, but beyond this 
our knowledge does not extend* 

89. Starting then, in our synthetical career, with 
the primordial atoms either of a single element, or of 
several elements, we are compelled to acknowledge 
the agency and intelligence and design of a creating 
and controlling Cause, who gave existence to those 
atoms, and impressed upon them those virgin affiui- 
ties or first laws of action, in obedience to which they 
entered into those primal combinations which consti* 
tuted the proximate elements of nature ; and these, 
again, received new laws of aggregation, which result- 
ed in other forms and qualities of matter. And thus, 
from step to step in the great architectural work, the 
delineating and directing finger of Omnipotence in- 
scribed the constitutional laws of every form, and by 
those laiirs imparted to each form its own peculiar 
nature and properties and powers, and defined the 
modes of conduct to all material action. But how far 
these rudimental combinations and arrangements 
travelled down from the deep bosom of eternity, before 
they reached the present visible and tangible state of 
things, it is impossible for us to ascertain, without a 
knowledge of the first-made forms of matter. Nor is 
it of much importance to my present purpose that we 
should know, since our ignorance in this respect does 
not obscure the great principle of my .reasoning. 
Those substances which we now call elements, are 
probably the results of many combinations of the pri- 
mordial atoms (66), and although most of them have 
hitherto resisteid the powers of analysis in the hands 
of man, it is almost certain that they are decomposed 
by the vital^ energies of organic forms (31), and per- 
haps also, in many of the operations of inorganio 

90. There is, however, the greatest probability that 
the pure gaseous form, or form of vapor, is that which 
matter ^in its progressive combinations first assumed 
within 'the bounds which lie between the known and 
the unknown of things ; and there does not appear 
to be any just ground of doubt that the first palpable 
form of matter was limpid water. * The form of our 
globe, and of the moon, and all the planets and celes- 
tial bodies,' says Dr. Arnot, 'demonstrates their 
original fluidity.' The laws of constitutional rela- 
tion between water and the vegetable and animal 
forms of matter, indeed the whole economy of nature 
strongly indicates, if it does not prove, that water 
was the first visible and tangible form of this material 
world. And Moses in his brief history of creation, 
tells us that before the heaven and the earth were 
formed, ' darkness was upon the face of the deep (or 
the abyss), and the spirit of Ood moved upon the face 
of the waters.' 

91. Water was regarded by the ancients as one of 
the elements of nature, and some, indeed, considered 
it the single original element, out of which all other 
material things were formed. Nor was it till the 
close of the last century that its compound nature 
was fully ascertained, and it was found to be formed 
by the chemical combination of two kinds of air or 

92. I have already stated (87), that modern chem- 
istry has distributed matter into more than fifty sub- 
stances, which in the present state of science are 
called elements. Among these are two, which are 
denominated oxygen and hydrogen gases. Oxygen 
gas or air, in its separate and pure state, is a little 
heavier than the common atmosphere, of which it is 
a component part, and is the supporter of animal res- 
piration, and the principal supporter of combustion. 
Remove it entirely from the atmosphere, and we could 
not breathe, and our lamps and fires would be im- 
mediately extinguished, and many other evils would 
result, which there will be occasion to notice in the 
progress of my subject. Hydrogen gas is about four- 
teen times lighter or less dense than the atmosphere, 
and is one of the most combustible substances known. 
If a quantity of oxygen gas be enclosed in one vessel. 



and a quantity of hydrogen in another, with a tube 
leading from each vessel and uniting in a common 
mouth, acid if the gases be permitted to pass out in 
certain proportions, and be fired at the mouth where 
they meet and mix together, a bright flame will flash 
up, and at the same time a heat will be produced, of 
sufficient intensity to burn iron like dry wood, with a 
brilliancy of light which the eye can hardly endure, 
and to melt down many minerals and other hard sub- 
stances which the heat of a common fire will scarcely 
affect at all ; the product of the combustion of these 
two gases is water. 

93. Thus, from two invisible aeriform substances 
which burn with such intensity of heat and brilliancy 
of light, water is formed by their chemical combina- 
tion in the act of combustion, and when thus pro- 
duced, is one of the greatest extinguishers of com- 
bustion known in nature, and is many hundred times 
heavier than the same volume of the gases from 
which it was formed ! 

94. Nor is it necessary to suppose, that the water 
first formed was in a turbid state, holding, in a semi- 
fluid solution, a chaotic mass of crude and undigested 
matter, which gradually settled into solid forms, and 
thus produced the rocks and finally the earthy mould 
which covers them. 

95. It is only the opinion that those different forms 
of matter which we call simple substances are, in 
their peculiar natures and properties, essentially and 
primordially different and distinct, which causes us 
to cling to the vague notion of a primitive chaos of 
partly fluid and partly solid matter, mixed together 
m a kind of semifluid paste or pudding, because, with 
our limited views of things, we cannot easily con- 
ceive how rocks and other solid substances could be 
formed, without different, original, and appropriate 
kinds of matter, adapted to the structure of such 

96. But if we keep in view the principles which we 
have been contemplating, and the truth of which may 
be considered as more than probable — that all the dif- 
ferent forms and substances and qualities of matter 
are but the results of different arrangements and ag- 
gregations of the same primordial atoms — we shiUl 
find no difiiculty in understanding how rocks and 
other solid substances could be formed from pure 
transparent water. Besides, it is a matter of con- 
tinual fact, that the various crystalline substances 
are so formed ; and certainly we cannot consider it 
more incredible that such solid substances should be 
formed from a limpid fluid, than that they should be 
formed immediately from thin and invisible air, which 
is a fact of frequent occurrence in nature and in art. 

97. The transformation ot fluids into solids, which 
seems to possess no properties in common with the 
fluids from which they were formed, is a very com- 
mon process in the latioratories of chemists, and by no 
means an unfrequent one in the great operations of 

98. It is not, therefore, in any degree necessary for 
us to suppose that matter, in it& first visible and tan- 
gible state, consisted of a chaos of all the rudimentarv 
substances mingled together in confusion, but still 
possessing each its distinct existence and peculiar 
character. Pure limpid water alone, with the sur. 
rounding atmosphere, and light and heat and electri- 
city, contains amply sufficient material for all the 
purposes of nature in the magnificent architecture of 
our world of things. 

99. Those substances which we call oxygen and 
nitrogen gases, being more primitive forms of matter 
than water, of course existed before it, and therefore 
the atmosphere, such or nearly such as now surrounds 
the globe, existed before the formation of the world 
of waters. 

100. When the intimate connection between light 
and heat and electricty and magnetism is considered, 

and when we take into view the important parts 
which these agents probably performed in the pro- 
gressive work of the original construction of the va- 
rious forms of matter, we are philosophically led to 
suppose that they were the next productions in the 
order of creation. And accordina^ to the Mosaic re- 
cord, after water was formed, light was commanded 
to be, and there was light ; and it is now pretty fully 
ascertained, that if light is not simply a peculiar ar- 
rangement and condition of the primary atoms com- 
mon to all matter ; if light and common matter are 
not convertible into each other, as suggested by Sir 
Isaac Newton, it does not emanate from the sun ac- 
cording to the doctrine of that distinguished philoso- 
pher, but is a substance so far independent of the sun 
as to be capable of existing without it. 

101. In intimate connexion with light, came heat 
and electricity and magnetism. These new agents 
being brought into operation upon fixed constitutional 
principles, by the almighty and creative Energy, 
began to act upon the atmosphere and water, accord- 
ing to laws of constitution and relation prescribed by 
infinite intelligence and benevolent design. 

102. Evaporation began to take place, and the 
waters ascended up silently in the invisible state of 
vapor ; ' and the waters were divided from the waters.* 
and the firmament was established. At the same 
time new laws of aggregation were brought into 
action in * the mighty deep,' and the limpid water 

began to arrange itself in the beautiful and Solid crys- 
tals of mineral structure. For even here, in this in- 
organic aggregation, intelligence and design preside, 
ordaining and exerting rigorous law ; and every par- 
ticle of matter, as by a kind of instinct, takes its con- 
stitutional place, with an order and precision and 
integrity inflexible as necessity and irresistible as 
omnipotence ! observing with the exactness of geome- 
try the lines and angles of the structure into which 
it enters, as if each particular atom were directed one 
by one, by the designing finger of the Almighty. 
And thus the fluctuating waters were composed into 
the ^ everlasting rocks,* varying in nice peculiarities, 
according to the delicate variations of the constitu- 
tional laws of aggregation. And thus the found- 
ations of the earth were laid and built up, and lifted 
their heads from out the bosom of the *■ vasty deep,' 
' and the waters under the heaven were gathered to- 
gether into one place, and the dry land appeared.'* 

103. Heat, and frost and moisture, and various 
other agents acting upon the rocks which rose above 
the face of the water, caused a disintegration of their 
surfaces, and by this means a body of gravelly earth 
was formed as a mitrix for vegetable seeds and roots. 
Thus was the inorganic world completed. Nice va- 
rieties of gaseous and fluid and solid formations, con- 
tinued to be produced by the ceaseless operations of 
nature. And deep in the bosom of the globe^ fires were 
spontaneously kindled, by which vast portions of the 
solid rocks were melted, and brought again into a 
fluid state, and earthquakes jtnd volcanoes were pro- 
duced : and by such means, the immense beds of un- 
stratified rocks were formed, and the superincumbent 
layers thrown into disorder, and hills and mountains 
were erected, and molten rocks poured out upon the 
surface of the earth. 

104. Such is the general hypothesis which one class 
of geologists have assumed concerning the formation 
of the globe. While another class, with equal confi- 

* Those geologists who oppose the idea that water was the first 
perceptible form of the matter of our globe, contend that the crys- 
tals of what are supposed to be the primitiye rocks, are much 
more like those which we know to be the result of fusion, than 
those resulting from solution. But the idea which 1 have ad- 
vanced in the text, is that primitive crystallization resulted flrom 
electricity or galvanic action on pure aqueous matter ; in which 
case the crystals would more resemble those which result flrom 
fusion than those from solution, but as a general Ikct, would be 
much more regular and perfect than either. 



dence, and with numerous facts which favor their 
positions, have embraced the hypothesis that the 
matter of our globe was originally in a state of thin 
vapor, produced by intense heat, and that, as this 
body of vapor gradually cooled down, it became more 
dense, and in due time the surface became so cool 
that the matter began to consolidate and form a crust 
of rocks, which slowly increased in thickness inwardly, 
while heat and moisture and frost and other agents 
acting on the external surface, caused a disintegration 
of the rocks as already stated ; and when some thou- 
sands of years had passed away, and numerous layers 
of stratified rocks had been posed upon the 
original crust, by the precipitation or deposition of 
matter held in aqueous solution, and derived from 
the disintegration of the primitive rocks, then the 
ptent fires in the centre of the globe became impa- 
tient of their confinement, and rose up in their wrath, 
and burst through their prison walls, now strengthen- 
ed by the continual accunmlations of hundreds of 
centuries; and thus, not only hills and mountains 
were formed, but islands and continents were lifted 
from the bottom of the ocean, and made dry land, 
and portions of the unstratified rocks or original 
crusts were thrust up through the superincumbent 
layers, and thrown out upon the surface of the earth. 
106. I say there are many facts which greatly favor 
this Plutonian hypothesis, so much in vogue among 
geologists at the present day : and yet I cannot feel 
convinced that the objections against it are not more 
powerful than the facts in favor of it. Besides, I con- 
ceive that every fact which the advocates for this 
hypothesis adduce in its support, is perfectly compat- 
ible with the aqueous origin of the globe. But after 
all, it is of little importance, to the argument which 
I have in view, whether the Plutonian or the Neptu- 
nian hypothesis is the true one ; since, in either case, 
the general positions which I have advanced concern- 
ing the original forms and primitive combinations of 
matter are equally sustained. Nor, indeed, is it of 
much importance to my argument, that any geologi- 
cal theory should be established. 

106. The great points I wish to prove are, first, 
that the natural elements of matter are very few in 
number, and probably a single one; — secondly, that 
essentially the same matter is common to all material 
forms both of the inorganic and organic world ; and 
therefore the essential difference between inorganic 
and organic forms of matter, is not in the matter 
Itself, of which they are composed, but exclusively in 
the constitutional laws of aggregation and arrange- 
ment ; — and thirdly, that all the affinities, properties, 
and laws of matter, established and brought into 
action during the formation, and up to the completion 
of the inorganic world, necessarily ended in inorganic 
aggregations and forms, and beyond which it was not 
possible for them to go, 

107. The first of these points I have shown to be 
exceedingly probable; the second is unquestionably 
true; and the third admits not the shadow of a 
doubt. To suppose that the action of inorganic affin- 
ities could terminate in organic arrangement, is to 
assume that it is possibe for the same thing to be 
and not to be at the same time ; and to say that 
organic affinities could grow out of any inorganic 
properties of matter, is equally contradictory and 
absurd. If inorganic affinities or properties are ex- 
erted, inorganic results necessarily take place ; and no 
combination of inorganic material causes, can pos- 
sibly produce an organic effect. For it is only by 
counteracting and overcoming and suspending the 
inorganic affinities, and destroying the inorganic ag- 
gregations, that matter can be brought into organic 
aggregation, and established in the organic constitu- 
tion. Hence it is always and to all extent neces- 
sarily true, that the inorganic affinities are directly 

'Opposed to the organic affinities ; and therefore the 

latter could, in no possible way, spring from the 
former, nor from any results of the former. 

108. The atheistical notions concerning the origin 
of organic forms of matter, and of mind, are there- 
fore utterly unphilosophical, and entirely destitute 
of any foundation in scientific truth, and all attempts 
to account for vitality upon any principles appertain, 
ing to the physical or chemical properties of matter, 
must necessarily end in error and absurdity. To say 
that life is the result of peculiar organization of mat- 
ter, is obviously and egregiously absurd ; because we 
Icnow that organization is always and necessarily the 
result of vital action ; and therefore, excepting the 
first act of creation, vitality has always produced 
organization, and propagated and perpetuated itself 
in and through organized matter; but has never 
been, and cannot, in the nature of things, ever be, 
produced by organized matter not possesssing life. 
And the notion that the organized matter of our 
world belongs to a state of things which has eternally 
existed, is entirely contradictory to all that we know 
of the nature of things. 

109. The inorganic world left to its^, with all its 
properties and powers in eontinual activity and per- 
petual operation, would necessarily have remained 
for ever within the precincts of inomnic law and 
structure. The solitary ocean would have rolled on 
in its eternal flow and ebb of tides, — evaporation and 
dowds and rain, — lightnings and thunders and tem- 
pestuous winds, and raging hurricanes, and wintry 
storms, — and spring and summer skies, and balmy 
airs, and bright and glorious sunshine, and sultry 
heat, — and congealing frost, — and night and day, 
would have succeeded in endless and unfertilizing 
rounds ; while on the surface of the solid and the 
liquid globe, and in its bosom, and deep within its 
bowels, the busy chemistry of inorganic nature 
would have carried on its unceasing processes, trans- 
muting substances, and multiplying the varieties of 
forms and properties; and kindling subterraneous 
fires to burst into volcanoes and to rend the globe 
with tremendous earthquakes, and heave the regu- 
larly concentric strata of its rocks into wild irregfu- 
larity and disorder ; disturbing thus the smooth 
rotundity of its surface, and producing lofty moun- 
tains and deep valleys, and ploughing channels for 
the streams and rivers, and scooping out new dwelling- 
places for the ocean : but, not a tree nor plant nor 
blade of grass, nor any other organic form of matter, 
could possibly have been produced by any or all of 
the affinities and properties and powers of that lonely 
and lifeless world ! 

110. Men, in the ^oomy or the sensual darkness 
of their minds, and in the temerity of indomitable 
pride, may speculate as they will, but sound philoso- 
phy and the truth of science pause on the confines 
of the inorganic world, and are compelled to acknow- 
ledge the necessity of an intelligent and designing 
Omnipotence, to superinduce new laws of action and 
arrangement, and establish new constitutions, by 
which matter shall be set free from the dominion of 
its more primitive affinities, and lifted up above its 
former state of being, and forced into arrangements 
and structures and tissues and organs and systems, 
entirely different from any of its previous forms, by 
the action of affinities which cannot co-operate nor 
efficiently co-exist in the least possible measure, with 
any of the inorganic affinities : nay, indeed, which 
cannot act, but to resist and subdue the inorganic 
affinities ; which cannot erect their own peculiar su- 
perstructures, according to their own specific econ- 
omy, without overcoming and demolishing at every 
step the affinities and structures of inorganic mat- 
ter (86). 

111. How, then, could any primitive condition of 
imnganic matter ever have produced, by any of its 
intrmsic properties or powers, « single blade o^ grasi^ 



or the simplest form of vegetable existence ? It is 
not possible! and such an opinion cannot be em- 
braced without a credulity which shuts its eyes against 
the light of science, and far exceeds the darkest 
superstitions of the human race. 


All fonns of matter composed of the same elements — Water the 
principal material Arom which vegetables are formed — ^The dif- 
ferent vegetable substances produced firom the same mate- 
rials — Bach, its fixed laws of constitution and relation — Animal 
bodies not produced by inorganic or vegetable affinities — 
Esseutially different — The ponstitutional economy of nature 
permanent — If man were cut off, matter could not reproduce 
him — Animal substances, how formed — The composition and 
properties of inorganic bodies — Organized bodies derive their 
existence from pre-existing organized bodies — Organic ele- 
ments, how formed and arranged — Organic bodies consist of 
both solids and fluids— They take the type of the bodies that 
produce them — Life a forced state — Vitality resists gravitation — 
Resists the law of temperature — Organic bodies return to inor- 
ganic forms of matter wheu life ceases— Hibernating animals, 
how preserved — Transmutation of substances — Life terminates 
in death— Mutability of organic forms— Properties common to 
all organised bodies — Difference between animal and vegetable 
bodies — Properties peculiar to animals — The use of chemistry 
to phjrsiology — ^Vitality decomposes chemical elements — The 
nature of things depends not on their matter but their con- 
stitution — Constitutional nature and relations of each and 

112. It is, then, as already stated (106), by dif. 
ferent aggregations of the same elementary atoms of 
which air and water, rocks and earth, are formed, 
that vegetable substances and forms are produced. 
Water is the principal material which enters into the 
vegetable structure. The atmosphere also affords a 
portion of the nutriment of vegetables ; and light 
and heat are concerned in the activity of vegetable 
life, and in vegetable growth, and qualities and forms. 
But all these substances, or forms of matter, on en- 
tering into the vegetable organic structure, forego 
their inorganic forms and characters and qualities, 
and become vegetable organic matter. The oxygen 
and hydrogen and carbon of inorganic chemistry, by 
virtue of new laws, new actions and new arrange- 
ments, become vegetable sap, and this, by various 
new arrangements lesulting from vital action, be- 
comes solid wood and bark and leaf and blossom, and 
color and odor, and fruit and resin and gum, etc., etc. 
But while these compose the vegetable structure, and 
while vegetable life exerts its controling energy, it 
cannot, with strictest propriety, be said, that there is 
any such substance as oxygen, or hydrogen, or carbon 
within the vital domain : these substances can only 
be detected as such, when they have been set free 
from the vegetable structure and arrangement, and 
have returned again to the inorganic state. 

113. Yet, notwithstanding vegetable substances 
have their fixed and peculiar laws of constitution 
essentially different from those of inorganic arrange- 
ment, there is, nevertheless, such an exact adaptation 
of the constitutions of these different structures to 
each other, that the most determinate and fixed and 
important laws of relation exist between them. 

114. Here, again, if the vegetable and inorganic 
world be left to itself, it is not possible for any, nor 
for all of its material properties and powers, sepa- 
rately, or combined, to produce animal life and 
structure and organization, and its self-nourishing 
and self-propagating economy. If inorganic affinities 
predominate, inorganic structure necessarily results. 
If vegetable organic affinities predominate, vegetable 
structure necessarily results. They cannot possibly 
co-operate, because they directly counteract each 
other : and if it were possible for them to be simul- 
taneously co-efficient, they could not act together in 
the production of a third substance, differing from 
inorganic, and from vegetable organic structure, and 
of m higher order of nature than either; but of ne- 

cessity, from the nature of things, they would srrwt 
each other and remain in belligerent equilibrio. Be- 
sides, if it were possible for laws of action and con. 
stitution to arise from any condition of inorganic 
and vegetable matter, by which animal life and 
structure and organization could be produced, such 
laws, in order to accomplish such systematic resuhi, 
must necessarily arise from the nature of things, and 
therefore, of necessity, must be as permanent in their 
existence and activity as the nature of things from 
which they spring. But such are the constitutional 
laws and relations of things, that they cannot essen- 
tially alter their natures without ceasing to exist; 
for the nature of things depends not on the matter ef 
which they are formed, but on the laws of constitution 
by whuih the matter is arranged (106). Hence, there- 
fore, if it were possible for laws of action and con- 
stitution to arise from any condition of inorganic and 
vegetable^ matter, by which animal structure and 
organization and function could be produced, then of 
necessity, in the nature of things, such laws would 
still continue to exist and to produce their results; 
and living animal bodies would not depend on the 
vital power and economy for their successive origina- 
tion, but on the physical laws by which they are 
first produced. Yet we know that these things are 
not so : and who with a sane mind can believe, that 
if every human being were, at this moment, destroyed 
from the face of the earth, matter, with all its inor- 
ganic and vegetable and animal properties and powers, 
could, in millions of years, or even an eternity of 
time, reproduce the human species, or rise a hair's 
breadth above the order of being which now exists 
next on the scale to man ? 

115. If animal matter were, in its ultimate ele- 
ments, essentially different from vegetable and inor- 
ganic matter, then might we suppose that obeying 
laws peculiar to its nature, it entered into an ar- 
rangement peculiar to itself, without opposing or in 
any manner interfering with the inorganic and vege- 
table affinities: but, when we know that animal 
matter resolved even to the experimental elements of 
chemistry, is in reality nothing but inorganic matter, 
common to all material forms and substances, we see 
that it is not in any possible degree the nature of the 
matter, but the constitutional laws of arrangement, on 
which all the forms and properties and peculiarities of 
material substances depend. Hence therefore, of neces- 
sity, the laws of arrangement from which animal 
structure results, are not only opposed to the laws of 
inorganic and vegetable arrangement, but altogether 
of a higher order ; superinduc^ by a Power extrinsic 
from matter, by an Intelligence adequate to the great 
designs of nature, and by a Power competent for the 
fulfilment of its desigpis. 

1 16. A truly philosophic and scientific mind cannot 
indeed, ask^for a more complete demonstration of the 
existence of an intelligent, omnipotent, and benevolent 
First Cause, than is afforded by an accurate know- 
ledge of the laws of the various material structures 
and forms, and modes of existence. 

117. By the controlling power of peculiar laws of 
action which overcome and suspend the inorganic af- 
finities, and which also demolish the vegetable stme- 
ture, matter is set free, or rather forced from its 
previous forms of aggregation, and compelled to take 
on the arrangement, and enter into the structure, 
and compose the organs of living animal bodies; 
where it remains in reluctant vassalage, till, having 
fulfilled the purposes of the system, in subservience 
to the vital economy, it is regularly discharged from 
the vital domain — or until the vital power is wholly 
worn out or overcome and destroyed, when it returns 
again to the more primitive dominion of iBorgsnie 
affinities and aggregations, there to continue in the 
simpler and more permanent forms of inorganic mat- 
ter, w be subject to its variout ohanges, until periuqpe 



it Ia again forced into the comparatively brief endur- 
ance of vegetable or ai^mal organic laws of life ; 
and 10 on» in the perpetual round of inorganic and 
vegetable and animal structure, matter takes its 
course, obedient to the various lavs which comprise 
the several constitutions of those forms. 

U8. Thus, from the same primordial atoms of 
which all vegetable and mineral substances are made, 
the living animal blood is also formed, simply by a 
different arrangement resulting from laws of action 
which neither existed in any of the previous forms, 
nor sprung from any of the previous conditions or 
properties of matter, but were instituted and estab- 
lished in a permanent economy by a supreme Intelli- 
gent and designing Power. By a different arrange- 
ment of the matter composing this same living blood, 
the cellular substance of the animal is formed. By a 
still different arrangement, the animal muscle is 
formed from the same blood ; and by a still different 
arrangement of the matter of the same blood, it 
formed the living animal nerve, which is the most 
remarkable for its peculiar properties and powers, of 
any known material structure. And thus every solid 
and every secreted fluid of the body is formed from 
the blood, by the peculiar arrangement o£ the atoms 
of matter ; and this is purely a result of vital power, 
acting and accomplishing its ends in direct opposition 
to the chemical affinities of inorganic matter, and 
differing essentially in its nature and effects from 
the vegetable organic economy. 

119. Notwithstanding, therefore, all material bodies 
and substances are formed from essentially the same 
matter, by different arrangements of its primordial 
atoms, yet, by virtue of their different laws of con- 
stitution, organic and inorganic bodies and substances 
differ essentially from each other in their natures and 

120. Inorganic bodies, resulting from the more 
primitive affinities and simple aggregations of mat- 
ter (106), may, according to the statements of che- 
mistry, consist of a single one of those substances 
which are called elements ; or of a combination of 
two of them ; or of four of them, in double binary 
compounds ; or of six of them, in triple binary com- 
pounds. They may also exist in the solid or liquid or 
gaseous forms; yet every organic body consists wholly, 
either of the solid or liquid or gaseous form of matter ; 
and all its parts are ahke in structure and properties, 
and may exist as well when separated into portions or 
broken into fragments, as when united in a single 
volume or mass. But whether solid, liquid, or g^as- 
eous ; whether composed of one or more of the chem- 
ical elements, the aggregations and arrangements of 
the atoms of matter in every substance take place 
according to fixed constitutional laws, and in a regular 
and determinate manner ; so that the intimate struc- 
ture of each form of matter is always true to its own 
nature. Still, however, the constitutional laws of 
aggregation in inorganic bodies do not define the 
shape nor determine the size of the general mass, and 
therefore, while their molecular arrangement is al- 
ways strictly determinate and true to their nature, 
their general mass is either regular or irregular in 
shape, and large or small in size, according to cir- 
cumstances, and the action of accidental causes, and 
without in the least degree affecting their nature or 
properties : and they are increased or diminished in 
size, or changed in shape, not by anv internal econ- 
omy of growth or decrement, but by the simple accre- 
tion of matter to, or attrition of, it from the surface. 

121. Organized bodies, as we have seen (106), do 
not result from the action of the more primitive af- 
finities of matter, but are produced by a permanently 
established constitutional economy, the intrinsic forces 
of which counteract and overcome those affinities, 
and bring the elementary atoms of matter into ar- 
zmngementi wholly different from those of inorganic 

substances (107) ; tmd the forces of this economy do 
not act, as it were, unembodied and at large on the 
natural elements of matter, but their operations are 
always confined to living bodies, consisting of a sys- 
tem of organs, in and by which they produce their 
peculiar effects, and transmute inorganic substances 
into the substances and structures and organs of liv- 
ing, vegetable, and animal bodies. All organized 
bodies, therefore, are, of necessity, produced only by 
the controlling power and action of the vital forces of 
living organized bodies ; or in other words, all organ- 
ized bodies necessarily derive their existence from pre- 
existing organized bodies. 

122. In the peculiar processes by which the vital 
economy transforms the common matter of the inor- 
ganic world into the organized matter of living bodies, 
those simple forms of organic matter are produced 
which are called the organic elements, and which, 
according to chemical analysis of dead vegetable and 
animal matter, are composed (generally speaking) in 
the vegetable of three, and in the animal of four, of 
those substances called the inorganic elements. But 
as the peculiar combinations and arrangements by 
which the organic elements are formed, can only be 
effected by the vital forces and actions of the living 
organs, so it is impossible by any other means or in 
any other manner to produce the organic elements. 

123. When the living body has elaborated its own 
elements from the various, and even very different 
materials on which its assimilating forces act, it dis- 
tributes them to every part of the system by an in- 
temal economy peculiar to organized bodies, and in 
the most r^^iar and determinate manner arranges 
them in its several structures and organs, and thus 
incorporates and identifies them with itself. 

124. These interesting processes and results require 
that organized bodies should be composed of both 
solids and fluids ; of solids differing in character and 
properties arranged into organs, and these endowed 
with peculiar functional powers, and so associated as 
to form of the whole a single system ; and of fluids 
contained in those organs, and holding such constitu- 
tional relations to the solids as that the existence, the 
nature, and the properties of both, mutually and ne- 
cessarily depend on each other. 

125. As the vital forces by which organized sub- 
stances are produced, always and of necessity act in 
and by the organs of living bodies (121), as intrinsic 
constitutional properties or powers, so the operations 
and results of the vital economy are governed and 
determined by the organic constitution of the body in 
which it acts; and hence, all organized bodies not 
only derive their existence from pre-existing organ- 
ized bodies^ but necessarily also take on the type of 
the bodies from which they spring, and are of the 
same internal and external structure and form; 
and when no disturbing causes modify the result of 
the general organic economy, they naturally come to the 
same size. And consequently, all organized bodies have, 
within a certain range, their specific proportions and 
shape and size ; by which, as a general fact, they are 
not only distinguished from inorganic bodies, but 
specifically from each other. 

126. Not only the intimate structure, but the gen- 
oral conformation of parts, and the adjustment of 
properties in organized bodies, therefore, depend on 
the action of the vital forces and the general control 
of the vital economy ; and life maintains its dominion 
over the organized mass, and preserves in all its parts 
an integrity of structure and of function, not only 
by counteracting and overcoming the inorganic affin- 
ities, in its processes of assimilation and organization, 
but by resisting the action of foreign powers and 
influences. For, while the chemical affinities of in- 
organic matter are more completely overcome and 
subdued by vitality within its own organic domain, 
chemical agents and the physical laws of nature are 



continually exerting their influence on liring bodiei, 
causing an expenditure of vital power, and tending 
to the destruction of the vital constitution, and the 
decomposition of the organized matter. 

127. From the commencement to the termination 
of the vital existence of organized bodies, therefore^ 
life maintains a continual conflict with opposing 
forces : and hence it has with beauty and propriety 
been said, that ' life is a forced state,'—' a temporary 
victory over the causes which induce death.* 

128. The common law of matter, which in our 
world causes all bodies to tend to the centre of the 
earth, acts equally on inorganic and organic bodies, 
and therefore, it is in direct opposition to this law, 
that vegetable vitality raises up the sap, and con- 
structs the vegetable form ; and almost every func* 
tion and action of animal bodies, is performed in 
opposition to the law of gravity. The ascending 
fluids ; the act of standing, and walking, and rais- 
ing the hand, etc., etc., are all vital performances, in 
opposition to the law of gravitation. 

129. Again, it is a common law in physics, that 
heat always seeks an equilibrium of temperature in 
contiguous bodies ; that is, the hotter body always 
imparts its heat to the colder one in contact, until 
they are both of the same temperature : and this law 
appertains to all forms of matter, inorganic and 
organic. Living bodies give off their heat to colder 
bodies in contact, the same as inorganic bodies, and 
but for their peculiar powers, would soon become of 
the same temperature of contiguous bodies or the 
surrounding medium. By virtue of vitality, how- 
ever, they are enabled to maintain a temperature pe- 
culiar to themselves — ^not by suspending or counter- 
acting the common law of heat, but by generating 
heat, according to the wants of the system ; or by 
disposing of its excess in the formation of vapor. Even 
the lowest order of vegetable life, while in a state of 
activity, preserves a temperature peculiar to itself ; 
and this is more remarkably the case with animal 
life, and especially in the higher orders of animal ex- 
istence. The temperature of the human blood, for 
instance, is, in a healthy, robust man, about ninety- 
eight degrees ; and it hardly varies two degrees from 
this point, whether the temperature of the surround- 
ing atmosphere be twenty degrees below zero, or two 
hundred and sixty degrees above it : but destroy 
vitality, and very soon the blood will be of the same 
temperature of the surrounding air. 

130. When heat acts on inorganic bodies, it raises 
their temperature by directly communicating itself, 
or its quality or condition, to them ; but living an- 
imal bodies mostly or entirely resist this action of 
extrinsic heat, and their temperature is very little, if 
at all, elevated by its direct communication to them as 
heat. When extrinsic heat, therefore, serves to ele- 
vate in any degree the temperature of the living an- 
imal body, it does it in a twofold manner : positively, 
and negatively. Positively, by acting as a stimulus 
on the nervous system, and through that, on the or- 
gans and vessels generally, and thus increasing vital 
and functional activity ; and negatively, by elevating 
the temperature of the surrounding' medium, and 
thus preventing the radiation of intrinsic heat. 
Hence, the more healthfully vigorous the vital power 
is, in animal bodies, the better are they enabled to 
sustain the extremes of cold and heat. 

131. Organic arrangement of matter, being as we 
have seen (106) the result of vital forces which 
counteract and suspend the more primitive affinities 
of inorganic matter, depends entirely for its perma- 
nence, on the controlling power of vitality ; hence, 
when organic arrangement is destroyed, it is always 
by the mastery of the inorganic affinites, asserting 
their prior claim to the organized matter : and con- 
sequently, organic bodies when they c^se to live, be- 
gin immediately to decay : or in other words> th^ 

matter begins to return to the dominion of inorganic 
affinities and laws, and to enter into inorganic agg^. 
gations and forms. But while vitality maintains its 
predominance, it resists the action of the principles 
of decay, and preserves the matter within its precints, 
in its living organic nature and condition and powers. 
Thus vegetable and animal bodies being deprived of 
their vitality (unless artificially preserv^) soon decay 
and pass into inorganic arrangements and forms of 
matter ; yet veg^able seeds and roots have been pre- 
served by their vitality for thousands of years, with 
all their properties and powers so perfect, that even 
after a lapse of centuries, on being placed in a genial 
soil, they have vegetated, and grown like the produc- 
tions of the preceding year. And, in like manner, 
some of the animal creation, such as toads and frogs, 
have been preserved by their organic vitality, in a 
state of suspended animation, for hundreds and thou- 
sands of ^ears ; and on being set free from their incar- 
ceration m the bosom of soud rocks, far beneath the 
surface of the earth, have awakened again from their 
living death, and exerted their powers of locomotion. 
But if the vitality of those bodies be extinct when 
they are first surrounded by the matter of the rock, 
and when that matter is in a fluid state; or if they be 
surrounded when not in a state of hibernation or of 
suspended animation, and their vitality be destroyed, 
the fluid enters into the cavities of the bodies, and by 
its peculiar qualities, so acts upon the organized mat- 
ter, that it foregoes its organic arrangement, and 
takes on the aggregation of the rock in which it is 
entombed, retaining only the general outlines of its 
animal form ; and thus becomes an animal petrifac- 
tion. Vegetable substances are also frequency petri- 
fied or transmuted in the same manner. 'I have 
often seen amidst quantities of mineral ore brought 
into this city for manufacturing purposes,' says Mr. 
John Far, an extensive practicu chemist of Philadel- 
phia, ' pieces of wood, which at one end were partly 
carbonated, in the middle completely carbonated, and 
at the other end changed into sulphuret of iron, hard 
enough to strike fire with a fiint.* 

132. Thus in every case, so long as vitality main- 
tains its dominion over the matter which is forced 
into its organic structure, it preserves that matter 
from the power of inorganic affinities, but when that 
conservating principle is destroyed, matter returns, as 
by a more deeply written instinct, to its more primi- 
tive and inorganic forms. 

133. Vitality, as I have already stated (108), is not 
in the least possible degree the result of pecuUar ar- 
rangements of matter, but the peculiar arrangements 
of matter composing organic bodies are always the 
results of vital action, and depend on vital power 
and vital action for their continuance; and hence, 
living bodies not only derive their origin from pre- 
existing beings like themselves (125), but also, in a 
perfect state, always possess faculties and powers 
by which vitality perpetuates itself, in connexion 
with organization, in the successive propagation of 
organized bodies. And hence also (126), when that 
peculiar condition of organized bodies on which the 
operations of the vital economy depend, is either vio- 
lently destroyed or gradually worn out, the vital ac- 
tions cease, and life becomes extinct ; and the individ- 
ual existence of the body terminates in death, and the 
matter composing it yields to the action of inorganic 
affinities, and dissolution and decay succeed. As a 
general law, therefore, organic bodies, from their 
very nature and condition, are less permanent in 
their modes of existence than inorganic bodies are. 

134. See, in yonder peaceful and silent retirement, 
that gray, moss-covered rock, rendered hoary and 
veueri^ble by the lapse of centuries, and deeply wrink- 
led in its ancient brow, by the waveless and noiseless, 
but swiftly gliding current of time. Beside it stands 

I in fuU ^e^^jm^ and early vfgor, a noble oak whose 




faurge and powerfiil branches stretch abroad, in bold 
defiance of the storms of heaven. In the shadow of 
that stately tree, and under the covert of that ven- 
erable rock, a little boy« full of health and buoyancy 
and vivacity of youth, is happy in the enjoyment of 
his childish play. To one who did not know the 
history of man,' or understand his nature, it would 
seem as if that human form, in all its health and ac- 
tivity and power, might be as permanent in its exist- 
ence as that tree and rock. 

136. Years pass away, and lo ! beside that rock, 
and in the shadow of that tree, leaning upon the 
handle of his scythe, in the full stature and sturdi- 
ness of manhood, he that was that boy, again appears. 
Health and athletic vigor ; energy of mind, and 
peacefiilness of heart; bright prospects, and sustain- 
ing hopes, in all the fulness of lifers prime, are his. 
He looks far abroad over his fertile fields, and in the 
dreamy sunshine of his soul contemplates the pros- 
perity and happiness of coming years. But in that 
bright prospective vista of his thoughts, there comes 
no intimation to his mind, that in those future years 
so full of present hope, old age with all its paralyzing 
and withering influences, will come upon him, to 
take away his strength and elasticity, and impair his 
senses, and, to him, throw over every thing in nature, 
the twilight mistiness, if not the melancholy, of de- 
clining life. But years pass on, and there remains 
that rock, unaltered in its aspect and its form, save 
where, perhaps, the violence of man hath made a frac- 
ture on its insensible front, and it may be, the in- 
clemencies of heaven — humidity and frost, and the 
eternal unebbing flow of time — have worn more 
deeply the wrinkles of its brow : and there that oak, 
in its full power and stateliness and verdant health, 
oontinnes still beside that ancient rock ; no marks of 
time*8 destructivenesi are on it ; save here and there, 
on ihe extremity of some long branch, a leafless and 
dry twig appears. But lo, where but as yesterday 
that boy was seen, in the spring-tide and joyfulness of 

nth, now stands an aged man, bowing in palsied 
»leness upon his staff, and thinking how like a 
hurried dream his life has been. He looks upon that 
rock and on that tree as the associates of his child- 
hood ; and they remind him of his youthftil days, and 
bring back upon his chilled and aged heart, some- 
thing of the warmer spirit of those years of childish 
cheeirfulness and hope : and it hardly seems reality to 
him, that such a change has passed upon him in the 
brief lapse of intervening time, which has stolen 
from him even as the oblivion of a single 
night ! The rock, the tree, and all the face of nature, 
seem the same as when in infancy he first beheld 
them ; but he is changed ! He feels that he is 
changed ! The bounding pulse — the elastic step — the 
buoyant spirit — they have passed away, and left him 
in the tottering feebleness of hoary-headed age ! A 
fisw more years pass on, and that old man is gathered 
to the dead, and his organic tenement returns to in- 
organic and insensible forms of matter; and other 
generations come to make acquaintance with that 
rock and tree, and pass through life with all its hopes 
and fears, and joys and griefs, from childhood to old 
age, and die and moulder back to former dust ! Thus, 
in succession, genera(j[ons rise and fall, till by and by, 
the years are numbered eveu of that troe ; and death 
begins to manifest itself in the leafless and dry branches 
of its top ; and soon its verdure and its foliage wholly 
disappear, and the dead trunk and limbs stand hoary 
as the aged man ; and in a few more years, that tree 
is prostrate on its native earth, and silently decays be- 
side that solitary rock, which still remains but little 
changed in form and size and aspect, from what it 
was, even centuries before the tree first sprang from 
earth within the precincts of its shadow. 

136. Thus organic bodies begin their existence, 
and gradually grow up to maturity ; and then decline 

and die, and decay, and pass into other forms of mat- 
ter, in comparatively brief periods of time ; while in- 
organic bodies more permanently exist, exempt from 
death, and from those internal changes and effects 
which impair and finally destroy the constitutional 
power of oiganic structure and arrangement. 

137. The properties already stated as peculiar to 
living organized bodies, are common to all vegetables 
and animals. All living material beings, vegetable 
and aninal, derive their origin from pre-existing 
bodies of the same kind ; and possess the faculties 
of nutrition and reproduction, and alike terminate 
their peculiar modes of existence by death. Yet the 
animal kingdom is as distinct from the vegetable, as 
the latter is from the mineral kingdom : and although 
animads partake of several physiological properties 
and powers and conditions, in common with vege- 
tables, nevertheless, the constitutional laws of arrange- 
ment in animal matter, differ as essentially from 
those of vegetable, as the latter do from those of in- 
organic aggregation. Hence, animal structure is of 
an entirely different nature from that of vege- 
tables, and possesses properties and powers peculiar 
to itself. 

138. The great fundamental endowments distin- 
guishing animals from vegetables, are, sensibility, 
consciousness of being, volition, and voluntary action 
or motion, out of which grow a number of im- 
portant and interesting faculties and peculiarities. 

139. According to the technical language of chem- 
istry, vegetable matter, as a general statement, is 
formed by a peculiar combination of carbon, oxygen, 
and hydrogen ; while animal matter is formed* by a 
peculiar combination of nitrogen, oxygen, hydrogen, 
and carbon. Several other simple substances are also 
said to enter into the composition of vegetable and 
animal bodies. But these statements are assuined 
rather for the convenience of theory than as being 
exact expressions of what is strictly true in the na- 
ture of things. The great fondness of modern chem- 
ists to acQount for all the phenomena and results of 
vitality upon chemical principles, has too frequently 
led them to trespass on the prerogatives of life, and 
thus retard the progress of physiological science, by 
preventing that investigation of the vital forces and 
actions, which is necessary to a full ascertainment of 
the laws of life. It should be ever remembered, that 
no organic substance can be separated from the vital 
control, and subjected to chemical experiment, with- 
out so essentially altering the character of the sub- 
stance, as to render it impossible for the chemist to 
afiirm, from the results of his experiments, with any 
degree of certainty, what is true or not true of the 
peculiar processes of the living organic system. It is 
therefore much more safe and philosophically accurate 
for chemists to say what inorganic forms or kinds of 
matter result from a chemical analysis of organic sub- 
stances, than it is for them to state that organic sub- 
stances are composed of such and such chemical ele- 
ments or kinds of matter. We know, it is true, that 
all material bodies are composed of that common 
matter of the world, which modern chemistry has 
distributed into more than fifty elements; and we 
know that in manufacturing its various organic sub- 
stances out of that common matter, the vital economy 
employs more of some of those elements than of 
others. We also know that some of those elements 
or forms of matter are much better adapted to the 
purposes of the living body than others ; but we have 
no right to assume that the vital forces possess no 
higher energies of analysis than are exerted by the 
chemical agents of the inorganic world; nor that 
their principles of combination in any respect resem- 
ble those of inorganic chemistry : on the contrary, 
we have reason to believe that vitality decomposes 
all those substances used in its economy, which chem- 
iBta call elements ; and that in arranging its various 

ii ■ I I ii n iii i i H i ■■■ ■ I T • I, . -r ^j 



organic substances and structures, its synthetical 
operations are very different from those of inorganic 
chemistry. It is therefore purely hypothetical to 
assert that oxygen, and carbon, and hydrogen, and 
azote, and other chemical elements, as such, combine 
in the vital processes, to form the various substances 
and structures of the organic system. Nevertheless, 
it remains equally true, that the only essential dif- 
ferences between the various organic and inorganic 
forms of matter, consist in, and spring from, the 
constitutional laws of arrangement which govern 
their component particles and caruHtute the pectUiar 
nature qf each form, 

140. The most interesting and important principles, 
therefore, which are presented to our consideration 
by these investigations, and which should make the 
deepest impression on every mind, are these : — The 


sult; and consequently, it is necessarily true, not 
only that each particular form of matter has its spe- 
cific laws of constitution, but also that the constitu- 
tion of each particular form is so exactly adapted 
to the constitution of other forms of matter, in rela- 
tion to which it exists, that the most definite, and 
fixed, and inseparable laws of relation are established 
between all material forms ; binding the universe to- 
gether in one great and intimate community of 
interests, on principles as fixed and permanent^ and 
as unalterable as the nature of things. 

141. Thus, the proximate elements of nature were 
constituted with definite relations to each other ; and 
so on, as matter travelled down from its unimaginably 
subtil, and almost spiritual essence (87)f combining 
(it may be^ its essence and its proximate elements 
in a thousand modes before it reached those forms 
which human science regards as simple substances), 
each peculiar form of matter, throughout all the 
range, was constituted with fixed and permanent re- 
lations to all other forms : and, continuing on in the 
progressive work of conformation, the same principle 
pervaded all material existence. 

142. Thus, water has not only its fixed and neces- 
sary laws of constitution, but also its constitutional 
laws of relation to the gases of which it is formed, 
and to every thing in the mineral kingdom formed 
from it ; and thus, the vegetable sap has its own pe- 
culiar laws of constitution, and its fixed and precise 
constitutional laws of relation to water and the at- 
mosphere, etc. ; and the woody matter, and bark and 
leaf, and blossom and color and fragrance and fruit, 
etc., of vegetables, have all their particular laws of 
constitution, and their definite laws of relation to 
each other, and to the sap and to the atmosphere, 
and to heat, and light, etc.: and thus, again, the 
animal blood has its fixed laws of constitution, and 
its equally fixed and necessary laws of relation, to 
the aliment from which it is formed, and to water, 
and the atmosphere, etc. ; and the bone, and carti- 
lage, and muscle, and nerve, and all other forms of 
matter in the animal system, have their fixed and 
necessary laws of constitution, and their necessary 
laws of relation to each other, and to the blood from 
which they are formed. 

143. There are also many interesting laws of rela- 
tion existing between the inorganic and vegetable 
and animal kingdoms, of a more general and obvious 
character, which spring from the constitutional na- 
ture of things. Thus the vegetable economy has its 
relations to the nature and qualities of the soil, and 
atmosphere — to climate and seasons — to day and night 
—to heat and gravitation, etc., etc. ; and the vege- 
table economy, to a great extent, elaborates from in- 
ornfBiiic matter, the substances on which animals 

subsist ; and in turn vegetables receive a portion of 
their nutriment from animal excretions. Carbonic 
acid gas, which is thrown off in such immense quan- 
tities by animal respiration and perspiration, is, when 
received into the lungs without a mixture of atmos- 
pheric air, almost instantaneously destructive to ani- 
mal life ; or, in other words, it is wholly unfitted to 
sustain animal respiration : but the vegetable econ- 
omy, at least during the day, decomposes this gas, 
and retains its carbon as vegetable nourishment, and 
sets free the oxygen, which is the peculiar property 
or constituent principle of the atmosphere that sup- 
ports animal respiration. 

144. But these important and interesting relations 
are too numerous, and in many instances too intricate 
to admit of a full exhibition at this time. I shall, 
however, have occasion to speak of some of them 
which are most important to my subject, when I 
come to consider those particular points to which 
they more immediately belong. Suffice it now to say, 
that throughout the universe of created things, the 
laws of constitution and relation (146) compose the 
great permanent net- work in whose sustaining meshes 
all material forms and beings subsist. And there- 
fore, every thing in nature is bound to its general 
condition, by laws innumerable, which cannot be 
violated with impunity. And man, whether he will 
acknowledge it or not, is, in his constitution and re- 
lations, such that he cannot move nor breathe nor 
exercise volition without obeyiog or violating penal 
laws I 


All solids fonned from fluids, in the mineral, v^etablf, and 
animal kingdom — Chemical analysis and physiology — Phos> 
pborate of lime in bones — Laws of vital combination unknown 
— From chyle and blood, solids formed — The department of tike 
physiologist, what ?— of the anatomist, what?— of the chemist 
what?— How far chemistry can aid physiology — Chyle, its cha- 
racter — all the body formed from it — its properties nearly the 
same, whatever the food — The blood — all tlie substances of the 
body formed from it— Three general kinds of solids — Cellular, 
muscular, and nervous tissues — Globular form of the elementary 
filaments — The nature and properties of the three general 
tissues — These form all the organs — Their distribution and 
arrangement in the system — Natural order of development — 
Internal organs — External frame — Great divisions of the body 
— Arrangement of the serous membrane — its character — The 
bones — their number and arrangement — Cartilages, their sta- 
tion, and uses— General skeleton — Original state of the bones — 
The structure and character of cartilages and ligaments — 
Properties of the muscle— distribution and ftinctions — Volun- 
tary and involuntary muscles — ^Tendons — Number of muscles 
— Arrangement of volimtary and involimtary muscles — Muscles 
not reproduced. 

145. It is an interesting fact, that so far as human 
knowledge extends, all solid bodies are formed from 
fluids. In the mineral kingdom, the internal struc- 
ture and general form of some solid masses indicate a 
previous state of fiision, or fluidity, produced by heat 
or electricity ; while others strongly indicate, if they 
do not prove, a state of previous solution, or aqueous 
fluidity of their matter. 

146. In the vegetable kingdom we know, that all 
the solid, as well as other substances in the plant or 
tree, are formed from the sap, which, in the radicles 
that absorb it from the earth, is apparently little else 
than pure water, and which is gradually changed into 
the vegetable nature, and determinately arranged in 
the vegetable structures, by the peculiar powers of 
the vegetable economy. And in the animal kingdom 
also, we know that all the solid, as well as other sub- 
stances composing the living body, are formed from 
the thin watery fluid called chyle, which is elaborated 
from the digested food of the alimentary canal, and 
gradually converted into living blood, and diffused 
throughout the system, and arranged into solids and 
secreted into other fluids, by the peculiar energies of 
animal vitality. 



147. When the chyle and blood, and bone and mus- 
cle, and the various other solids and fluids of the sys- 
tem, have been elaborated by the vital economy, 
chemists take these several substances and subject 
them to chemical experiment and analysis, and when 
they have resolved them to the simplest forms pecu- 
liar to the decomposition of animal matter, they de- 
nominate the substances thus obtained, the organic 
elements ; and these again are resolved to the ulti- 
mate chemical elements, or purely Inorganic forms 
of matter. And thus we are furnished with a chem- 
ical nomenclature of the elements that compose the 
living animal body. And learned physiologists, tak- 
ing these results of the chemical analysis of dead 
animal matter, gravely attempt to account for most 
or all of the operations and effects of the living 
organic economy, on the principles of inorganic chem- 
istry ; and to teach us what chemical elements com- 
bine, and in what proportions, to form the several 
substances of the organic system. But it must be 
perfectly obvious that most of their reasoning is 
purely hypothetical; for it assumes that the exper- 
mental elements of chemistry are the real elements 
of nature; or, at any rate, the vital forces cannot 
decompose them ; and, therefore, that the chemical 
decomposition of dead animal matter, demonstrates 
the vital composition of liuing animal matter. But, 
if any given number or proportions of the chemical 
elements, as such, combine to form any one animal 
substance, why is it not possible for the manufactur- 
ing powers of human science, with the same elements, 
to make any approach to the results of the vital 
processes (51) ? 

148. The atheistical philosopher sneeringly tells us 
that the human bone was not made by a God, as the 
igrnorant superstitiously believe, but that it is com- 
posed of gelatin, phosphorate of lime, etc., and that 
these are formed by peculiar combinations of oxygen, 
hydrogen, carbon, azote, phosphorus, etc. But can 
such philosophers take these elements and compose 
the human bone ? Or do they seriously believe that 
there is any power or means in the material universe, 
by which the human bone can be composed, except 
the vital power and economy of the living animal 
system ? Whether phosphoric acid and lime, as such, 
enter into the vital composition of the animal bone or 
not, it is not possible for the atheistical philosopher to 
prove 'that they do; and science affords him less 
evidence of the fact, than it does that the peculiar 
economy by which alone in nature the animal bone 
is formed, was originated and established by an Intel- 
ligent Creator. Nor would it be an easier matter for 
the chemical physiologists to demonstrate that the 
gelatin which so largely abounds in animal bodies is 
formed from the albumen of the blood by a chemical 
process which abstracts from it a portion of its carbon, 
as such; nor, indeed, can it be proved that oxygen, or 
carbon, or any other chemical element, as stich, passes 
through the vital operations into the living results, 
retaining its peculiar nature and properties, or with- 
out entirely foregoing the nature and qualities which 
it possessed as an inorganic substance. 

149. All we know with certainty is, that when 

{>roper substances are received into the appropriate 
iving and healthy organs of the animal system, they 
are, by powers and processes peculiar to that system, 
converted into chyme, chyle, and blood, and from the 
blood, into several distinctly different solids and fluids, 
possessing each its peculiar nature and properties ; the 
solids being so arranged as to form the several organs 
of the system, and the fluids being contained in those 
organs in such state and conditions as the welfare of 
the vital domain requires. 

150. To ascertain as fully and as accurately as pos- 
sible, the properties and powers of the living solids, 
separately, and the functional powers and perform, 
ances of the several organs formed by particular 

arrangements of these solids, and the nature and 
purposes of the fluids, and the general and particular 
laws and conditions which govern and affect the vital 
economy ; in short, to ascertain as far as possible, all 
the properties and powers and operations and effects 
of the living body, is the appropriate business of the 
physiologist. When the bodv is dead, the dissection 
and description of its several parts, organs, tissues, 
etc., is the appropriate business of the anatomist; 
and the analysis of the dead animal matter into prox- 
im^te or ultimate elements, is appropriately and only 
the business of the chemist. 

151. Chemistry, therefore, can tell us what forms of 
inorganic matter result from a chemical analysis of 
dead animal matter; but she cannot tell us what 
forms combine to compose the living organ. She 
cannot inform us a priori whether mineral or vege- 
table or animal substances are best adapted to the 
alimentary wants of man ; nor can she with any cer- 
tainty direct us in the selection of even those sub- 
stances which experience has proved to be nourishing 
to the human body. She can decompose the atmos- 
phere, but she cannot tell us which of its elements 
qualify it to support animal respiration. If, by 
reason of impaired functional power in the human 
stomach, foreign acids should be generated in that 
organ by the action of inorganic aflinities, chemistry 
can inform us what will neutralize those acids, but 
she cannot tell us whether the alkalies which she pre- 
scribes, will not do more mischief to the living tissues 
of the organ, than the acids she seeks to neutralize ; 
and, therefore, she cannot tell us whether her very 
remedy will not be a powerful means of perpetuating 
the evil she seeks to remove : in short, she can in no 
respect, from her knowledge of the chemical ele- 
ments, or their laws of combination in the living 
body, tell us what is salutary or baneful to the vital 
weal. All this we learn only from the living body. 

152. While, therefore, all due honor is paid to the 
highly interesting and important science of chemistry, 
the sciences of physiology and of therapeutics should 
be exceedingly cautious how they invoke her aid. So 
far as chemistry can assist the physiologist in ascer- 
taining and defining the external relations of the 
living body, she is useful to him ; but more than this 
she cannot do, with that certainty which should in- 
spire his confidence. 

153. The most simple form of the animalized mat- 
ter composing the living body, is the chyle, which is 
elaborated from the digested food in the alimentary 
canal. This, when it first enters the radicles of those 
capillary tubes which conduct it onward towards the 
blood-vessels, is a very thin pearl-colored fluid, ap- 
parently homogeneous, and, by chemical analysis, is 
almost wholly resolved into water. And so far as 
chemical scnitiny has been able to discover, this fluid 
it almost precisely the same, whether elaborated from 
vegetable or animal food.* As it proceeds along the 
vitalizing tubes, it gradually becomes more and more 
albumenous and fibrinous; and with scarcely any 
appreciable difference in regard to these properties, 
whether the food be vegetable or animal ; but in re- 
gard to vital properties and effects, differing very 
considerably, as we shall see hereafter (466). 

154. MHien the chyle enters the blood-vessels, it 
approaches very nearly in character to the blood, 
which is itself apparently a very simple, homogene- 
ous fluid, the chief constituents of which are essen- 
tially albumenous; and of which, four fifths may 
be resolved to water by chemical decomposition. 

155. From the blood, the vital economy elaborates 
all the substances and forms of matter composing the 
animal body, constructing, with marvellous skill and 
wisdom (with reference to final causes), the blood, 
vessels and the alimentary tube, with the assemblage 

• See Note to 465. 



of organs associated -with it for the purposes (*f nu- 
trition, and the outer wails of the body wkh iti 
hmbft and organs of external relation. 

\5>S. The solid formn of organized matter thus inex. 
pHcahlv atid wonderfully elaborated by the vital 
eootiomy from the fluid blood, consiatintT of mem- 
branes, and tverrea ai^d m uncles and tendons and 
ligaments and cartilages and bone^, may all be re- 
duced to three general ktndi of substances — the f^ela- 
Unous, the fibrtnoiis, and the albumenous ; which, 
in the simplest language of modern physiology, are 
denominated the cellular, the musculaBj &nd the 


157- Some eminent physiologists assure us that the 
elementary structure of the animal tissues* ii a deli- 
cate arrangement of minute globules ; and that this 
is alike true of the cellular, musrukr, and nervous 
tissues (Fig. 1), Indeed, it is Fig. i. 

said that the £iiid as well as the 
solid parts, both of animals and 
plants, abound in these minute 
globules. In regard to the si^e 
of these gJohuleH, there is const* 
derable difference of opinion. Is 
bas been asserted by some, that 
a globe of about the eight thou, 
sandth part of an inch in diam- 
eter, is the eleinentary organic 
molecule of which every solid of 
every animal body is formed. 
Others contend that the size of 
the molecule;^ differs in the dif- 
ferent tissues, and even in dif- 
ferent parts of the neryonis system, 
— being, it is said, larifest in the brain proper, some- 
what smaller in the Httle brain,^ still smaller in the 
medulla oblnngataj smaller still in the spinal marrow, 
and smallest and most opaque of all in the nerves* 
These views m^j be correct ; but in the present state 
of our knowledge on this subject, we cannot rely with 
entire conBdence on the results of microscopic ini-esti- 

\5B. The gelatinous substance, in its various forms 
of proper cellular tissne, membranes, ten don Sj liga- 
ments, cartilages, etc., is the most simple of all the 
anima! solids, and the lowest in the scale of vitality 
and vital endowment. Its properties are cohesion, 
fledb^lliy, elasticity; and in some of its forms, ex- 
tensibility. These properties are, none of themf pe- 
culiar to 'organized matter ; yet the elasticity of the 
cellular tissue, which is a very important power in 
the vital i\inctions, is, probably, to a very considerable 
extent^ a vital endowment ; as it is much greater in 
the living body, than it is after life is extinct. 

159. The muscular tissue, composed of the tibrinous 
substance, is of a higher order of animali^ation and 
vital endowment than the cellular tissue. It possesses 
the two important vital properties of excitability and 
contractility. The former renders it capable of being 
acted on hv stimulants, and the latter, of contracting 
or shortening its length, under the action of stimu. 

160, It is impossible to say how far we can subject 
the animal tissues to our analytical investigations, 
without effecting an eg^ential change in their nature; 
and therefore we cannot with entire certainty affirm 
that the organized substance which we esamine and 
on which we experiment, is precisely the same as 
when constituting a healthy portion of the living 
body. It is under this disadvantage and incertitude 
that we always necessarily labor when we attempt 
to ascertain the elementary character of any of the 
animal solids ; or even of any of the results of vital 
action : and it is to a considerable degree under this 
ditadvantagej that physiologista affirm that the ner- 
vous tissue is essentially albumenous. But, as I have 
already stated, it is of comparatively little importance 

to the physiologist to know the chemical composition 
of the animal soHds. It mainly concerns him to know 
the vital properties and powers and functions of those 
solids when composed and arranged into organs r and 
in regard to these, there is little necessity for igno^ 
ranee or uncertainty on any important poinc. 

l^L The nervous tissue is the highest order of 
organized matter, and is endowed with the most 
peculiar and wonderful vital properties. In the de- 
scriptions of an atom fr it is said to consist of two 
apparently distinct substances. The one is sometimes 
called cineriiiouBj because it is generally the color of 
ashes ; sometimes cortlcalj because it Ues on the sur- 
face of the brain !ike the bark of a tree ; and some- 
times, from its apparent consistency, it is called pulpy, 
n is said to appear under a powerful microscope, to 
he principally composed of a congeries of blood- 
vessels. But the truth is, the real structure and 
character of this substance is little understood. Some 
consider it a kind of matrix or ganglion by which the 
real nervous substance is produced and re-enforced 5 
while others believe it to be the more refined and 
exalted part of the nervous substance, in which the 
sensorial power more especially resides. All this, 
however, is nothing but conjecture* 

162* The other substance, from its resemblance to 
marrow, is called medullary, or In contra-distinctioa 
to the cineritiouSj it is called the white substance, 
and more recently it has been called the Hbrous sub- 
stance, in contra-distinction to the pulpy. It is of 
iirmer consistence than the pulpy, and the matter 
of which it is composed has» in our own day^ been 
ascertained to be arranged in the form of minute 
and delicate fibres. 

163. In every portion of the nervous system* which 
constitutes a distinct nervous apparatus, the pulpy 
substance is found associated with the medullary or 
fibrous, in some of its parts. Sometimes investing 
the surface, as in the case of the brain ; and some- 
times situated more internally, as in the spinal 

164. The peculiar vital powers of the nervous 
tissue are two, the nervous and the sensorial 

To the nervous belong the vital properties con- 
cerned in the functions of digestion, ahsorption, res- 
piration, circulation, secretionj organization or the 
processes of structure, and the production of animal 
heat. The transmis^loti of external impressions to 
the centre of perception, and of the stimulus of voli- 
tion to the voluntary muscles^ have also been classed 
among the nervous properties, but it is questionable 
whether the former of tnese two powers or functions 
does not more strictly belong to the sensorial power 
of the nervous system. 

165.^ To the sensorial power belong consciousness, 
sensation, the perception of external impressions and 
internal affections, reflection, volition, and other 
faculties called intellectual. 

166. Sensibility is generally considered the funda- 
mental sensorial power ; yet the brain, which is 
regarded as the more special seat and centre of the 
sensorial power, is, in its own proper substance, en- 
tirely destitute of sensibility or the power of sensation, 
in the ordi n ary m ean i ngoftheword. Animalsensibil- 
ity,in the physiological signification of the term, is the 
powerof sensation in the living nervous tissue,and sen- 
sation is an affection of the living tissue, of which the 
centre of perception is not only conscious, but always 
rel^rs it to some particular locality. Animal sensa- 
tion, therefore J not only makes the mind conscious of 
a body, but of parti cu far parts of the body. This is 
not necessarily true of the sensorial power. We may 
gaze on an interesting and absorbing scene, or sink 
into a deep reverie, and lose all consciousness of a 
body, and be only conscious of a mental existence^ 
We ihink^ it is true^ and we are conscious of our 
thoughts ; but we are not conscious of the organjo 



machinery of our thoughts, and still less do we refer 
our thoughts as sensations to any particular part, or 
organ of the brain. At such times we are not even 
conscious of a brain, nor of a head, nor any thing of 
a corporeal nature. To say, therefore, that sensibility 
is the fundamental sensorial power, is to give the 
term sensation a very broad signification, and to con- 
found things, between which, in the common under- 
standing, there are very important differences. 

167. These three general tissues; the cellular, 
i muscular, and nervous, together with the more solid 
, matter of the bones, compose all the organs and parts 
•of the animal system; and, in entering into the texture 
:of the several organs, each tissue carries with it, and 
retains during life and health, its own peculiar vital 
properties, and these together, become the funda- 
mental principles of functional power in the organs. 

168^ The cellular tissue constitutes a kind of reti- 
culated frame-work to the whole body (fig. 2); giving 
shape and propor- p|g^ 2. 

ition to each particu- 
lar organ, and con- 
nezion to all; and 
entering so intimate- 
ly and extensively 
' into every part, that 
if the other sub- 
stances were entire- 
ly abstracted, the 
cellular tissue would 
perfectly preserve, not only the general outlines of 
the body, but the definition and proportions of each 
particular organ and part. 

169. Every bone partakes largely of this substance 
in a spongy or cellular arrangement, the interstices 
of which are filled with a fluid, separated from the 
blood, which becomes hard, and gives the peculiar 
solidity to the texture. Some of the bones are united 
by this substance in the form of elastic cartilage, or 
fibro-cartilage, as the vertebrae of the back, the ribs 
to the sternum, etc., and the articulating surfaces of 
the bones are also sheathed with cartilage : and the 
joints are strongly secured, and different bones bound 
together by another form of the same substance, called 
ligament. This last form is likewise expanded into 
a fibrous membrane, which surrounds every bone in 
the osseous system, and also surrounds the cartilages 
and forms sheaths for the tendons. 

170. Besides this distribution to the bones, carti- 
lages and tendons, the cellular tissue forms sheaths 
for every muscle and for every fibre of which each 
muscle consists, and principally composes the tendons 
and tendonous expansions which connect the muscles 
with the bones. Every fibre, and fasciculus, and cord, 
of the nervous system, is alsa separately enveloped in 
a delicate 
sheath of 

Fig. 3. 

cellular tis< 

sue (fig. 3); 

and the brain 

and spinal 

marrow are 

wrapped in a membraneous texture of the tame 


171* The different tissues, in their arrangement 
in the texture of the several vessels and viscera of the 
body, are connected together by the cellular tissue; 
and, in fact, this substance principally composes the 
solid part of all the vessels and viscera of the system : 
and finally, each individual organ is enveloped, and 
every internal surface is Uned, and the external sur- 
face of the body is covered with membranes composed 
of this substance. 

172. With very limited exception, if any, the vital 
contractility of the muscular tissue, is the only ele- 
ment of positive motion in the living animal body. 
All yolantavy motion, and most, if not all, involun- 

tary motion, depends on this vital property of the 
muscle. Hence the muscular tissue is distributed 
where motion is required. The bones are incapable 
of motion within themselves, and consequently no 
muscular tissue enters into their texture. But they 
serve as levers of voluntary motion, and therefore the 
muscles of voluntary motion are connected with them, 
and attached to them, in such a manner as that the 
contraction of the several different muscles produces 
the various motions required. The windpipe, m^t- 
pipe, stomach, and intestines, are also furnished with 
muscular tissue. The heart is principally muscular, 
and the diaphragm is mostly composed of muscular 
tissue. Several other internal organs are supplied 
with this tissue. The arteries and veins are said, by 
some anatomists, to be destitute of it, and yet it is 
very certain that they possess the power of con- 

173. The nerves, being the more peculiar and im- 
mediate instruments of vitality, preside over the 
functions of the vital economy ; and, consequently, 
they are distributed to every part of the system where 
a vital function is performed ; accompanying the 
blood-vessels in all their ramifications, and being 
most intimatdy associated with every muscular fibre 
and filament. 

174. In the order of nature, the blood-vessels with 
their appropriate and presiding nerves, are first pro- 
duced, and these immediately commence the structure 
of the alimentary tube with its accompanying organs, 
furnishing each with its due supply of cellular, mus- 
cular, and nervous tissue, according to its particular 
office in the system, and the powers required for the 
performance of its special function. At first, the 
several internal organs are, in a measure, so many 
distinct and independent formations or systems, 
which become more and more connected as their de- 
velopment advances, and finally they become so inti- 
mately associated as to form of the whole assemblage 
a single system. In the mean time, a wonderfully 
constructed tabernacle is in preparation for them. 
The spinal column, and the arching ribs, with their 
investments of muscle and membrane, form the hol- 
low trunk, which encloses, supports, and protects 
them. The head, and then the upper extremities, 
and the lower extremities, and the organs of special 
sense, and the external skin with its appendages of 
hair and nails follow in their order. 

175. For the better protection of the organs, and 
for other important purposes, the cavity of the body 
is divided by the diaphragm into two apartments 
(Fig. 41). The upper one is called the thorax, and 
the lower one, the abdomen. The thoracic cavity, 
extending from the neck to the lower extremity of 
the breast-bone in front, and somewhat lower at the 
sides and back, contains the lungs and heart and a 
portion of the large blood-vessels, and the meatpipe. 
The abdominal cavity contains the liver, stomach, 
intestinal canal, pancreas, spleen, kidaeys, etc. (Figs. 
4. and 31.) 

176. For the still farther security of the several 
parts, and the general well-being of the whole, a 
peculiar texture of the cellular substance, called the 
serous membrane, completely lines both cavities of 
the body, and then facing back upon itself, it is ex- 
tended and folded in such a manner, as to envelope 
each organ separately, and, in a measure, to insulate 
and confine it to its proper place. Thus, in the 
thorax or chest, the serous membrane, here called the 
pleura, besides lining the cavity throughout, includ- 
ing the upper surface of the diaphragm, faces back 
upon itself, and surrounds each lung, and passes 
double across the chest from the breast-bone to the 
back-bone, forming a septum or double partition 
between the lungs, called the mediastinum, and there- 
by completely encloses each lung in a sack by itself, 
the one on ua right and the ot&w on the left tide of 



the thorax* The two Uniinffi or sheets of membrane 
whiob form the middle partttion are separated at the 

rig. 4. 

a. "Lexge blood-vesiiisls. 
h. Eight luDgr. 
f . LcfE lung. 
d. Heart. 
ff.e, Diapliragmi. 

/. /. LivcTf turned tip. 

h. Large blood-vessel m the 
i.i. Intestinea, 

lower part of the chest, to receive the heart between 
tbe^. This or^n is also surrounded by its own 
pecaliar membrane called the pericardium* The se- 
rous membrane which lines the Inner surface of the 
abdomen, and envelopa each opg^an of that cavity, has 
the general name of peritoneum; but its particular 
parts are designated by term a stgriiiicant of the 
org-ani invested. Thus, the part which embraces the 
Intestinal tube» and holds tts con volutions in their 
relativ^e position^ ia called the mesentery^ mesacoloDj 
etc. (FJg, 5* See also fig, 35], 

Fig, 6, 

a» Thft dotted line TvpreEienting ^e ieroiu iAeia1»r«aa lining 

the WfiUi of thfl ftbdomlDAl ca^itj, 
m. The mesentein^. 
i, The inEestine, Burrounded by the sqtqum membraAfl wklch 

fartna ita peritoneal coaL 
V. The tplne^ 

J 77- ^Tj regard to the particular anatomy and phy- 
sjoloiry of the lerous membrane there is much differ- 
ence of opinion. Some describe it as being abundantly 
supplied with nerves and veaselSj both being co tor- 
less, and the latter containing a colorless ftuid, and 
performirtg the office of exbalants and absorbents; 
mud this they consider fully proved by the fact 
tbftt the serous membrane is capable of a high 

degree of inflammation and morbid sensibility ; as in 
pleimsy, peritonitis, etc. On the other hand. It is 
asaerted with equal confidence, tha^ this membrane 
is entirely destitute of both vessels and nerves^ and 
that fluids pass through it by infiltration or imbibi- 
tion. Those who entertain this opinion, of course 
deny that this membrane can bo the seat of inflam- 
mation and morbid ^^nsibility. They contend that 
the inflammatory diseases, attributed to the serous 
membratie, have their seat in the subjacent tUsue, 
and that such is the thinness and transparency of the 
serous membrane, that the inflamed aspect is seen 
through it^ and gives it the appearance of being itieJf 

17s* Be the truth as it may in regard to this dis- 
puted point, it is of very Uttle importance as a mat- 
ter of practical knowledge. In a healthy atate, at 
leastj the serous membrane has no animal sensibility. 
Its surface, external to the organs, but internal to 
itself, is exceedingly smooth, and is continually lubri- 
cated by a fluid which is either exhaled from its ve^. 
sels or passes through it by infi It ration from the sub- 
jacent vessels. By these means, contiguous organs 
are enabled to move with ease upon each otber, and 
the adhesion of contracting parts is prevented. On 
the side of the membrane, next to the organs and 
the parts which it lines, it is everywhere surrounded 
or covered with a f^pongy cellular substance, ^hich 
contains more or leHs of adipose or fatty matter, 
according to the condition of the body. In fleshy 
people, large quan titles of fat accumulate in many 
parts of this tissue (50S). 

179. The bones wbica compose the solid frame- 
work of the bodvj and serve to give it shape and firm- 
ness, and to form its cavities and its organs of prehen- 
sion and locomotion, are of various forms and sizes» 
Some of them are hollow, and their cavities are lined 
by a cellular membrane, which contains an unctuous 
substance called marrow^ the use of which is not cer- 
tainly known. The whole number of bones in the 
body is two hundred and fifty-six ; of which fifty-six 
belong to the trunk, sixty-siie to the head, sixt^'-eight 
to the upper and sixty-six to the lower extremities. 

ISO. Of the bones of the trunk, twenty-nine, and 
in some instances thirty, are employed in the con- 
struction of the spinal column or back -bone* Twenty- 
four of these are called the true vertebrae, and the 
other five are called the false vertebrje, or the sacrum 
and coccygia ; those last being concerned also with 
the hip bones in the formation of the pelvis or basin 
at the bottom of the trunk, and constituting the base 
on which the vercebiial column rests. Of the true 
vertebraj, seven belong to the neck, twelve to the 
back, and five to the loins ; and are accordingly dis- 
tinguished by the terms cervical, dorsal, and lumbar 
vertebrsft, from the Latin cerviitj neck, dorsum, back, 
and lumi^m, loins. These hones have somewhat the 
shape of a ring, with a roundeil body in front, and 
several projections from the arch behind ; one run^* 
ni ng di recti v back yj _ g 

which is calfed the 
spine, and two 
running obliquely 
backward, with 
which the ribs 
form one of their 
two posterior 
points of attach.- 
ment. {Fig. 6,) 
The vertebrffi are 
therefore so con- 
structed, that, 
when arranged in 
their proper order, 
they form both a 
column of support 
to the body, and 



8 canal for the spinal marrow. Between all of these 
bones is interposed an elastic fibro-cartilag^nous sub- 
stance, which, with surrounding ligaments, unites 
and binds them to each other in such a manner as to 
give the column considerable flexibility and elasticity, 
and at the same time secure to it all the supporting 
power of a solid bone. In the most natural, easy, 
and graceful position of the body, the spinal column 
is not erect, but waved or cunred ; and such is its 
elasticity, caused by the intenrertebral cartilages, 
that an individual is sometimes an inch taller when 
he rises in the morning than when he retires at 
night. (Fig. 7.) 

Fig. 7. 

:vj^, >■ 




body of vertebrsB, and one to the transverse process 
or oblique projection. They droop as they proceed 
forward, so that their anterior extremities are consi- 
derably lower in their natural position, than their 
posterior. The upper seven, called the true ribs, are 
united directly to the sternum or breast-bone by car- 
tilages. Of the remaining five, called the false ribs, 
three are Joined in front to each other and to the 
superior ribs by curved cartilages, and the two lowest 
are not in any way connected with the sternum, and 
are called floating ribs. (Fig. 8). 

182. Of the sixty-six bones which belong to the 
heady seven enter into the formation of the strong 
globe or skull which contains the brain, and which 
rests upon the top of the spinal column and receives 
the head of the spinal marrow through a large fora- 
men or opening at its base. Four small bones con- 
stitute a part of the auditory apparatus of each ear. 
The rest, beside the thirty-two teeth^ are employed 
in forming the upper and lower jaws, the cheeks, the 
nose, the palate, etc. There are in each jaw sixteen 
teeth ; of which there are on each side two front, 
one comer, and five cheek teeth. (Fig. 9.) 

Fig. 9. 

Bones of the head and spinal column, divided on the middle line 
so as to show— a, the brain; b, the little brainy g, the medulla 
oblongata; c, d, the spinal marrow. 

181. Attached to each side of the twelve dorsal 
vertebra are twelve ribs, which, together with the 
breast-bone, form the cavity of the chest. Most of 
the ribs have a doable attachment behind ; one to the 

i, the incisores, or cutting teeth. 
c, the cuspid, or comer tooth. 
b, the bicuspids, or small cheek teeth. 
ff, the molar, or large cheek teeth. 

a, the rudiments of the permanent teeth before they emerge 
from the jaw. 

^ 183. To the upper extremities belong, on each 
side, the shoulder-blade, the collar-bone, the long 
bone of the upper arm, the two bones of the fore arm^ 
the eight imail bones of the wrist, the five of the body 



of the band, the fourteen of the fingers and thumb, 
and the smaU appendage to the thumb-joint. 

184. To the lower extremities belong, on each side, 
the hip-bone, the long bone of the upper leg or 
thigh, the two bones of the lower leg, with the pa- 
tella, or knee-pan, the seven small bones of the ankle 
and heel, the five bones of the instep or body of the 
foot, the fourteen of the toes, and the small appen- 
dage to the great-toe-joint. 

186. At first, before the solidity of the bony struc 
ture is required by the condition of the animal, the 

Slace of the bones is entirely occupied by cartilages 
aving the precise shape of the bones to which they 
afterwards give place, except that they are none of 
them hollow. As the time approaches when the con- 
dition and functions of the organized system will re- 
quire the support and protection of the solid bone, the 
process of ossification commences at many different 
points, and continues on, till the whole osseous sys- 
tern is completed. But the cartilages are not wholly 
expelled from the system. Enough are retained to 
serve the purposes of union and general and particu- 
lar elasticity. As life advances, the bones gradually 
become more dry and hard, and in old age, and in 
some kinds of disease, they become vitreous and very 
brittle. In every instance where two bones are 
united, cartilage is interposed between them and 
forms the union : in some cases firmly, as in the 
sutures of the skull, in other cases admitting flexion, 
as in the back-bone and ribs. In all the moveable 
joints the articulating surfaces of the bone are 
covered with dense and highly-polished cartil- 
ages, which are continually lubricated by a glairy 
fluid called synovia; by which means the joints 
are enabled to act with great ease and little 
friction. Cartilage is also employed separately 
from the bones iii forming some of the cavities, 
as the larynx, wind-pipe, part of the nose, etc. 
All the cartilages, except the articular, are, like 
the bones, surrounded by a fibrous membrane 
called the perichondrium. Anatomists differ 
much in regurd to the vascular and nervous 
endowments of the cartilages. There is no reason 
to believe, however, that they have any other 
nerves than those which belong to the texture 
of the vessels concerned in their growth and 
nutrition (230) : and, accordingly, they have in 
health no animal sensibility (294), nor in health 
do their vessels contain any red blood. In early 
life, the cartilages are very soft : they gradually 
become drier and harder : and in old age they 
lose much of their elasticity and become brittle; 
and some of them ossified, or converted into bone; 
especially those of the fixed joints, as the sutures 
of the skull. 

186. By this interposition of cartilaginous sub- 
stance between the bones, many advantages are 
gained. Besides the flexibility of the spinal 
column and the yielding of the ribs and other 
bones, friction is prevented in the joints, and a 
general elasticity is imparted to the frame; 
greatly assisting in running and jumping, etc., 
and to a very considerable extent, protecting us 
from injury by breaking the force of blows, falls, 

187. The ligaments consist of an assemblage 
of strong fibres composed of the cellular tissue. 
They are employed in connecting the articular 
ends of the bones and cartilages : and in secur- 
ing the moveable joints, in such a manner as to 
prevent displacement, and at the same time, to 
allow of all necessary motion. Some of them are 
situated within the joint, like a central cord or 
pivot; some surround it like a hood, and con- 
tain the lubricating, synovial fluid ; and some 
are in the form of bands at the side. 

188. The ligaments bind the lower jaw to the 

temporal bones, the head to the neck, extend the whole 
length of the back-bone in powerful bands, both on 
the outer surface and within the spinal canal, and 
from one splnoua process to another ; and bind the 
ribs to the vertebrae, and to the transverse processes 
behind, and to the breast-bone in front, and this to 
the collar-bone, and this to the first rib and shoulder, 
blade, and this last to the bone of the upper-arm at 
the ihoulder-ioint, and this to the two bones of the 
fore-arm at the elbow-joint, and these to the bones 
of the wrist, and these to each other, and to those of 
the hand, and these last to each other, and those of 
the fingers and thumb. In the same manner, also, 
they bind the bones of the pelvis together, and the 
hip-bones to the thigh-bone, and this to the two bones 
of the leg and knee-pan, and so on, to the ankle and 
foot and toes, as in the upper extremities. And thus, 
the whole osseous system is united and bound toge- 
ther in the most powerful and admirable manner ; 
so as to possess, in a wonderful degree, mobility and 
firmness ^Fig. 10). The ligaments, like the cartila- 
ges, are, m health, destitute of animal sensibility ; 
and, like them, are more soft and yielding in early 
life, and become more dry, and rigid, and inflexible, 
in old age. 

189. The musdes, commonly called the flesh, which 
clothe the bones with symmetry and comeHness, con- 
stitute a considerable part of the whole bulk of the 
body. To a carelesi observer, they seem to consist of 

Fig, 10. 

The Skeleton. 



& confused mass of fleab, Burroimdlng^ and adhermg to th« banes ; 
but the icientifio iri^uiner finds every part of the muscular sys- 
tem, to be arranged into orgaui, in the most regular and deter- 
minate manner- On divesting- the body of its integument or skin, 
diitinct masses of flesh are seen running in various directions 
(Fig* 11)* Some are Tery broad and thin, some narrower and 

Fig. n. 

Fifi. VL 

The Trunk di?ested of the skin, ehuwing the muBcks, £f, t, c» etc. 

thicker^ and some are more rounded* Some are of uniform siz^e, 
and some are large in the middle and tajjcr towards the extre- 
mitieSj and Kome spread out like a fan* Some are long, and some 
short. Some punning parallel with the bones, and some more or 
Jess obliquely or transversely. These are called muscles; and 
each of them is surrounded by its o«n separate sheath of gauze- 
like cellular lifisue, the interstices of which are repositories of 
fatty matter. If this sheath be carefully opened, the muscle is 
found to be composed of a number of parallel fasciculi or bundles, 
each of which is likewise surrounded by a celhilar ^eath. If, 
again, one of theao be opened, a number of parallel fibres appear, 
which are aluo separately enveloped in cellular sheaths : and each 
of these fibres is composed of a number of minute parallel fila- 
ments (Fig. 12), 

lUO. There is the utmost discrepancy of opinion among anatom* 
istB, in regard to the elemeutary muscular fiJament. Some assert- 
ing that it is large enough to bo perceived by the unassisted eye j 
and others, that it is too small to lie discerned under the most 
powerful microscope. Some say that it is hollow, and others affirm 
that it Is solid* Some assure us that it is a continuous, uinform 

thread, «tnd others contend that it ii & 
delicate arrangement of minute globules, 
surrounded by a soft alburoeaous sub- 
stance, and appearing like a string of 
fine beads. But these points are of little 
importancetous. Ifwecanfully ascer- 
tain the vital properties and functional 
power* of the musclej and know on what 
these depend, and bow they are affected 
by those cauaes which are under our 
control, we possess essentially all the 
knowledge in regard to the nature and 
structure of the muscular filament, that 
can be of practical utility to the world. 

19U I have said (lo&) that the vital 
properties of the muscle are — Ist, sus- 
ceptihility, or a peculiar kind of or^anio 
sensibility to stimulants; 2nd, contracti- 
lity, or the power to shorten its length 
underatimuiation, Theseaie general ly 
regarded as a sinsfie property, or power^ 
and denomirtated muscular irritability. 
But they are obviously different powers. 
The one is a power to receive an im press- 
ion ^ and the other a power to ai^t under 
that impression, and they are both vital 
endowments of the muscle. In regard 
to muscular contraction, physiologist* 
do not agree. Some say that, when the 
muscle contracts, its fibres are bent in a 
waved direction, and have a knotted 
appearance ; and others assert that there 
is a longitudinal condensation of the 
substance. Some think the volume of 
the muscle is increased by the act of con- 
traction, and some assure us that it is 
not* But it is rtiongh for us to know, 
that the living healthy muscle, in all its 
forms and situationSj has vital contrac- 
ttHty, which is essentially the samCj and 
subject to the same laws, In all the parts 
and distributions and appropriations of 
themuicular system. Stime phplologist* 
contend that the muscle also possesses 
the power of active extension ; but the 
opinion Is not well supported, and is 
probable incorrect, 

192, The vital properties of the mus- 
cle are rapidly eithausted by action, uiid 
therefore it Is requisite that they should 
be continually replenished or sustained. 
This depends mo&t directly and imme- 
diately on the artei lal blood ; and con- 
sequently it is necessary that the mus- 
cle be constantly and freely supplied 
with that fluid, Acoordinglyj numer* 
nna and capacious arteries a're distri,< 
buted to the muKcles, penetrating them 
in every direction, and extending in 
countless ramifications to the smallest 
filaments, and conveying to the muscular 
system a very large supply of blood, 
to replenish its CKhausted energies, and 
to nourish its substimce. Veins every- 
where accompany the arteries to receive 
their unappropriated blood, and conduct 
it back. to the heart; and thus, a con- 
tiiiual stream of fresh arterial blood is 
poured through all the muscular tissue. 



\9^, The nervea which are distributed to the mus^ 
cles uf voluntary motioD, are of three kinds. 1. These 
that accompany, and beleag to^ the hi ood- vessels, and 
preside over their functian^. Tfae^e are enly cou- 
cemed m maintainiiig those coDditioBs a;id in pro^ 
ducing those changes in the blood which are necetsary 
to the welfare of ihe miiKcIe. 2. Tho^e that conv^ey 
to the musole the stimulus of the wii,l. These are 
supplied in great d umbers, and they divide and sub- 
divide till they are too small to be detected. These 
only act to stimulate and exhaust tbe musde. 3. The 
nerves of animal sensibility, that convey to the animal 
centre of perception those impressions by which the 
mind is informed of the action and conditions of the 
muscles, and of external tact, etc. These are fur- 
nished In small numherK^ and hence the muscles 
possess but little animal sensibility. None of these 
three kinds of nerves can be concerned in imparting 
directly and immediately to the muscle its peculiar 
vital properties. Those properties, therefore, belong 
to the intrinsic Titality of the muscle : and this vital- 
ity can only be maintained by constant supplies of 
arterial blood, in an appropriate condition ; and this, 
as a permanent fact, requires the presence and integ- 
rity of all the nerves described. A degree of muscular 
contractility, however, remains, sometimes a fuU hour 
after the extinction of animal iSfe. 

194. The muscles of the body are divided into two 
classes, in the descriptions of anatomy- Those of 
T^oJuniary motion, and those of involimtaiy motion. 
The former are also called the muscles of animal life, 
and the latter the muscles of vegetative or organic 
life. The muscles of voluntary tnotion, or of animal 
life, generally invest the bonea^ and are mostly on the 
outer parts of tbe body> and greatly abound in the 
limbs. The muscles of involuntary motion belong to 
the vascular system, and the digestive and respiratory 
apparatus. Some of the muscles of voluntary motion 
attaoh themGelves immediately to the bones | but most 
of them terminate tbeir two e^itre mi- 
ties in a fibrous arrangement of cellu- ^^^' ^^' 
lar tissuej called tendon, and by these 
tendons, or ten don on s expansions, are 
attached to the bones (Fig. 13.) Some 
anatomists suppose the tendons are 
formed by the continuation and con^ 
densation of the cellular sheaths which 
Burround the muscular fibres (170). 
^ 195. In their texture and proper- 
ties, the tendons differ very little from 
the ligaments. Tbeyare composed of 
small white fibres closely united to 
each other, and are surrounded by 
shej^tbs, lined by a membrane which 
secretes for them a lubricating fluid. 
They possess little elasticity or e:lten- 
s)bihty, have no animal sensibHity, 
and but few vessels, and these not 
discemiblein an ordinary state. Like 
the cartilages and ligaments, they are 
more soft and elastic in early life than 
at a later period, and become dry and 
rigid in old age, 

I9fi. The tendons being attached to 
the muscles at one end, adhere at the 
other to the periostium, or membrane 
which surrounds the bones, and 
whidi unites them to the bones i and 
thus they become the media through 
which the muscles act on the bones. 
Some of them ar© very long, and ex- 
tend to parts considerably removed 
itmn the muscles, as in the upper and A bideps nmscle, 
lower extremities. This arrangement ormufldoharing 
■ecu res many mechanical advantaees ^^° tendom at 
to the system^ and very greatly con- ^^ ^^^ oiher. 
tributes to the symmetry and beauty 

of the body, by accumulating muscles into large 
masses in some places, and withdrawing them from 
others, and thereby giving the beautifully curved 
outlines of the trunk, limbs, small ankles, wHsts, 
etc. The tendons are usually found only at the ex- 
tremities of the muscles, but they are sometimes in- 
serted in the middle, dividing the body of the muscle 
into two or more parts, as in the under jaw, the neck, 
diaphragm, etP. The end of the muscle which is 
attached to the most fixed point is called its head or 
origin, the fleshy mass is the body, and the end 
attached to the moveable point, is its termination. 
Some of the musdes are only attached to the bones at 
one extremity; and some being circular, have no 
direct attachment to the bones. Both of these East 
named kinds are found in the face, surrounding the 
mooth, etc, 

197. As the muscles have only the power to pro- 
duce motion by their contraction, they are so arrang- 
ed as to act as antagonists to each other, some dis^ 
placing a part and some refplacing it : some flexing or 
bending a iimbj and some extending it : and, there^ 
fore, they are termed the abductor and adductor — the 
flexor and the extensor muscles. The flexor muscles 
are considered to be generally more powerful than the 
extensors, and hence when the win. ceases to act, a$ 
in sound sleep and death^ the body and limbs ar^ 
partially flexed or bent. 

19B. According to Meckel, * there are in the nor- 
mal or proper state of the body, two hundred and 
thirty-eight different muscles, six of which are com- 
posed of two parts, which unite on the median line, 
and two hundred and thtrty-two are in pairs ; so that 
the whole number of the voluntary muscles are four 
hundred and seventy.' These are so arranged and 
adjusted, as to position and connexion, that by the 
contrat^tion of the different pairs or individual tnus^ 
cles all the voluntary motions of the lower limbs are 
performed. The function of respiration, which, to a 
certain extent, is both voluntary and involuntary, also 
employs some of these muscles. 

199. The muscles of involuntary motion are much 
more simple in their external form than those of 
animal life ; and encept in the heart, they have no 
appearance of tendons. Tlieir fasciculi, fibres, and 
filaments are not distinct and parallel to each other, 
but continually interlace, and consequently are much 
shorter than the fibres of the vofuotary muscles. 
Their fibres are arranged in several superimposed 
layers, and these layers are most generally transverse 
or oblique ; and form rings round the cavities which 
they circumscribe. The circular fibres or rings are 
nearest each other at the orifices of the cavities, and 
are stronger than the longitudinal or oblique fibres. 
The involuntary muscles do not antagonize or act in 
opposition to each other ; but they either act in con- 
ceit, or so as not to counteract each other; ns their 
office is to diminish the cavities in length and caliber; 
both of which may be done simultaneously. Some of 
the muscles or fibres, however, act alternately or suc- 
cessively, as in the heart and intestines. The invo- 
luntary muscles are even more abundantly supplied 
with vessels than those of animal !ife, 

200. The mnscles of the body, like the cartilages, 
ligaments, tendons, and other forms of the cellular 
tiSBtie^ are at first very soft, and gradually become 
more consistent and powerful ; ajidj in old age, they 
gradually become more and more dry and rigid» 

201. The muscular substance when once destroyed 
is never reproduced; but when the muscles are 
wounded with or without a loss of their substance, 
the breach is healed, and the parts united by a pecu- 
liar arrangement of cellular tissue, which ti "wholly 
insensible to the action of stimulants. 




The nerrous lyttem the mott important portion of the body— 
The more immediate organism of vitality— Through the nerves 
vitality acts on all the other tissues and substances of the body 
— Nervous system subject of great interest— Difficult to study — 
Physiologies properties common to all living bodies— Vege- 
tables and animals — Different degrees of consciousness and 
voluntary motion in different orders of animus— Organs of 
sensation and locomotion — of internal and external relation — 
their functions— Animal bodies have two classes of functions — 
of nutrition— of voluntary motion— How far are they dependent 
on a nervous system! — Have vegetables nerves? — Brain and 
spinal marrow^ etc., supposed to be the nervous system of man 
— errors of the opinion— Natural law and order of development 
— Human bodies without a brain and spinal marrow — Errors 
firom experiments on living animals — Brain and spinal marrow 
passive in the development of the body — Must be some other 
system of nerves — Nerves of organic life, their development, 
distributions, arrangements, and functions — General order of 
the development of the several parts of the body — Nerves of 
organic life preside over all the function of development, and 
nutrition, etc.— Composition of the ganglions— Ce^ebro-spiiial 
system — its order of development — distribution — airangement 
and functions. 

202. The nervous system is, in many respects, the 
most interesting and important portion of the human 
body. It is the more immediate organism of vitality, 
and the vital operations, and the intellectual manifes- 
tations : and hence it has been said, that the nervous 
system constitutes the man ; and, that the bones and 
muscles, and the whole assemblage of internal organs, 
with their various functions, are only intended to 
sustain and serve the nervous system. 

203. Vitality, however, is by no means peculiar to 
the nerves ; but, in various degrees, it pervades all 
the tissues of the living body; and the blood is a 
living fluid : and the chyle also, especially in its 
more advanced stage of assimilation, possesses a mea. 
sure of vitality. Nevertheless, the nerves are more 
highly endowed with vital properties and powers, 
than any other substance of the body : and they are, 
in the animal kingdom at least, most evidently and 
immediately the instruments of vitality, in all the 
operations of its wonderful economy. 

204. By the vital powers of the nerves, the proper, 
ties of the other tissues are called into exercise, and 
the functions of all the organs are performed. The 
food is digested into chyme, and thence into chyle, 
and thence into blood ; and the blood is transformed 
into the various solids and fluids of the system, and 
at the same time the temperature of the body is 
regulated (173). 

205. By virtue of the vital endowments of the 
nerves, we perceive our internal wants, and external 
condition, and relations ; and act upon the muscles, 
and through them upon the bones, in our voluntary 
motions. And by virtue of the peculiar and m vHteru 
ous endowments of the nervous substance, we think, 
and reason, and feel, and act, as intellectual and moral 
beings (530). 

206. It is not surprising, therefore, that the neN 
▼ous system of man has ever been the subject of 
peculiar interest to the anatomist and physiologist ; 
nor, when all the difficulties of the subject are con- 
sidered, is it wonderful that a great diversity of opi- 
nion and theory has always obtained in regard to it. 
Among those difficulties, the almost impossibility of 
carrying our enquiries within the vital domain, with- 
out disturbing the vital economy to such an extent 
as to throw the utmost uncertainty over the results 
of our investigations, is by no means the least. Yet 
it is to be apprehended that this difficulty has been 
too much disregarded by those who have boldly, and 
even rudely, invaded the precincts of life. Had those 
physiologists who have experimented so freely and 
extensively on living animals, always duly appreciated 
the force of sympathies in those bodies while under 
their experiments, they would probably have been 
saved from many erroneous conclusions ; or, at least, 
would have asserted them with- less confidence. 

207* I have said that all living bodies possess those 

faculties by which their nourishment and growth are 
eflTected, their temperature regulated, etc. (137). 
The vegetable seed, by virtue of its own vitality, ex- 
cited to action by a genial soil and ocher appropriate 
circumstances, puts forth its little roots into the earth, 
and absorbs foreign matter, and converts it into the 
substances and textures of its own organism ; and 
thus an economy is established, by which the trunk, 
and branches, and twigs, and leaves, of the giant oak. 
are gradually and fully developed, and all the vital 
operations of the tree maintained, until the condition 
on which the continuance of the vital action depends 
is worn out, or destroyed, and then death ensues. 

208. Drawing its nourishment from the earth, into 
which its roots penetrate, and from the atmosphere 
which surrounds it, and, in none of its final causes 
requiring a voluntary change of place, nor the per- 
formance of any other voluntary function, the tree, 
by nature, is fixed to the spot from which it springs, 
unconscious of its being, and without any organs of 
external perception and of voluntary motion. And, 
so far as those vital operations are considered by 
which chyme and chyle and blood are produced, and 
the blood circulated throughout the system, and the 
body, in all its parts nourished, and growth and de- 
velopment effected, and the temperature regulated, 
and all the other functions of organic life sustained, 
the animal differs but little from the vegetable : and, 
in health, is equally destitute of animal consciousness. 

209. In the lowest orders of animal existence, the 
Zoophytes approach so near, in all respects, to vege- 
tables, that naturalists long doubted whether they 
belong to the animal or vegetable kingdom. They 
are but dimly conscious of their being ; and are nou- 
rished by means which scarcely demand faculties 
superior to those with which the vegetable is endowed. 
But the higher orders of animals, being nourished by 
substances whieh are not only external, but separated 
from them, require both a perception of the internal 
wants of the system, and the faculties by which they 
can perceive, and approach to, and seize, the external 
substances by which those wants are supplied. Hence, 
organs of sensation, and of locomotion, and prehension, 
subject to voluntary control, are necessary as organs 
of externa] relation ; the primary office of which, is 
to perceive and procure the materials by which the 
body is nourished, and place them within the reach . 
of those organs of nutrition, by which the whole sys- 
tem is built up and sustained in all its powers and 
operations; and, also, to perceive and avoid, or with- 
draw from those causes or means, by v^hich the vital 
interests and the comfort of the body may be dis- 
turbed and destroyed ; and, having fulfilled these 
duties, the organs of external relation have no other 
immediate concern with the internal organic functions, 
except so far as their own welfare and integrity de- 
pend on the general welfare and integrity of the 
whole system. And this is true of all the higher, as 
well as of the lower classes of animals. 

210. There are, therefore, in organized bodies, two 
general classes of functions, and a corresponding orga- 
nization. The primary class, consists of all those 
functions which are concerned in the nourishment, 
growth, temperature, and general sustenance of the 
body, as an organized being. The secondary class, 
consists of those functions which minister to the wants 
of the primary class, and are established with refer- 
ence to the relations between those internal wants 
and the external supplies, and to the general external 
relations of the body. The functions of the primary 
class, I have said, are common to all organized bodies, 
both animal and vegetable; but those of the secon- 
dary class are peculiar to animals. 

211. The important question then is : do the funo« 
tions which are common to all organized bodies de- 
pend on a system of nerves, or are they performed 
independently of any nervous system ? 



212. It is a disputed point among physiologists, 
whether there is a system of nerves in vegetables or 
not. Some have asserted that they have been able 
dearly to discover a simple system of nerves in vege- 
table bodies ; while others declare that there is no- 
thing in vegetables which approaches to the nature 
4nd character of a nerve. That there is nothing in 
vegetable bodies which approaches to the nature and 
character of an animal nerve, cannot be doubted : for 
the whole molecular arrangement of organization, 
and all the vital operations and results of the vege- 
table, differ essentially from those of the animal; 
and therefore it is impossible that the organic struc- 
ture and properties of any of the vegetable tissues 
should be the same as those of the animal. Never- 
theless, it may be, and probably is t^ue, that there is 
a tissue in vegetable bodies which in functional cha- 
racter corresponds with the nervous tissue of animals, 
as nearly as the functions of vegetables and animals 
correspond in their processes and results. Be this as 
it may, however, it is entirely certain, that as the 
v^etable derives its nourishment from the earth, 
into which its roots penetrate, and has none of those 
external relations {j^hich require voluntary motion ; 
so it has none of those organs of external relation, 
which are concerned in perception, locomotion, and 
prehension ; and has nothing which, in structure, or 
properties, or functional character, corresponds with 
the cerebro-spinal system of nerves in animals. 

213. The nervous system of the human body has 
generally been considered as consisting of the brain 
and spinal marrow, with their numerous cords, 
branches, and twigs, dispersed over the whole orga- 
nized system: and these have been supposed to 
preside over all the varied operations and manifes- 
tations of life. 

214. Some anatomists and phvsiologists have con- 
tended that the brain is the original point of nervous 
development, from which spring, as from a grand 
root, the spinal trunk and all the branches and twigs 
of Uie nervous system : and these have considered the 
brain as the great centre of nervous, as well as sen- 
sorial power ; or as a kind of vital galvanic battery, 
which continually generates nervous energy, and dis- 
tributes it through nervous conductors to the several 
organs of the body, according to their functional 
necessities ; presiding in this manner, alike, over all 
ihe vital functions of the system. The opinion which 
has been more generally entertained, however, is, 
tJiat the spinal marrow is the grand original centre or 
uds of the nervous system, and that the brain and 
all the nervous cords, branches, and twigs of the 
lK>dy, spring from, and in a measure depend upon it. 
But if either of these opinions were correct, then it 
would necessarily be true, that in the original develop- 
ment of the body, Uie brain or spinal marrow would 
be the first-formed portion of the system, and come 
earliest to maturitv of form, size, and consistency, 
and of functional cnaracter and power. For it is a 
law of nature, in the development of organized bodies, 
that those parts are first produced and brought for- 
ward to a functional capacity, which are most essential 
to Uie earliest operations of the vital economy. But we 
know that, in the establishment of an economy, by 
whidi an animal body is to be developed, the first 
thing necessary is a presiding centre : the next thing 
is t^e blood-vessels, over the functions of which that 
centre presides, and by which the development of all 
tiie other parts of the system is effected. If, there- 
fi>re, the brain or spinal marrow were the presiding 
centre of vital operations, in the formative pro- 
eessea of the bodv, then it would necessarily 
^dUow, that all tne branches belonging to this 
centre would issue from it, and go out with the 
blood-vessels, to preside over their functions, in the 
formation of other parts, and to enter into the texture 
of parts thus constructed. But this is not true. So 

far is the brain or spinal marrow from being the first- 
formed portion of the system, that all the other parts 
of the body are formed, and considerably developed, 
while the brain and spinal marrow are jet in a fluid 
state, not more consistent than the white of an egg, 
and utterly incapable of exercising any functional 
power; and so far are the nervous branches, which 
have been supposed to issue from the spinal marrow, 
from investing the blood-vessels and presiding over 
their functions, that they are almost totally distributed 
to the voluntary muscles and to the outer surface of 
the body. 

216. But nature has not left us in the dark on any 
of these points. Where her normal operations have 
failed to instruct us, her abnormal exploits have 
afforded complete demonstration. Children have been 
born without a vestige of a brain or spinal marrow ; 
and I have known one instance, in which all the 
parts of the body were regularly and healthfully 
developed, except that there was no brain, nor spinal 
marrow, nor even a trace of a spinal canal ; the ver- 
tebrae being entirely solid. Such children, of course, 
cannot live after respiration becomes necessary ; be- 
cause respiration, though strictly speaking, an invo- 
luntary function, is yet, for important reasons which 
will be hereafter stated, immediately connected with 
the nerves and muscles of animal life ; or of voluntary 

216. Some distinguished physiologists, because they 
could not tear the brain and spinal marrow from the 
living animal, without arresting the functions of 
organic life, have insisted that those organs preside 
over these functions. But such physiologists might 
have been saved from their error, had they con. 
sidered that the assemblage of organs constituting 
the animal sytem, is more of a republic, or a confede- 
ration, than an absolute monarchy; and that the 
powers of that system are so delicately adjusted and 
so nicely balanced, that any considerable violence 
done to a particular part — and especially an important 
part — is necessarily felt as a disturbing cause, over 
the whole system ; and often to such a degree as to 
destroy the balance of power, and arrest all the 
functions of life, without by any means proving that 
the injured part is the centre of life, or that it is the 
organ which presides over the vital functions of the 
system. Ten thousand such experiments, therefore, 
are of no weight against the single fact that nature 
has produced ajbody in all other respects perfect, but 
destitute ^^ a brain and spinal marrow ; and yet 
evincing, by every appearance, that its organic life 
had continued till respiration became necessary. 

217' It follows of necessity, then, that the brain 
and spinal marrow, with their nervous appendages, 
stand rather in the relation of an effect than of a 
cause, to the formative and conservative operations 
and economy of the animal system : and we must 
therefore conclude, either that this economy in 
animals, as in vegetables, has no apparent nervous 
system which presides over its functions ; or that, in 
animals there is an apparatus, or system of nerves, 
which, so far as the internal interests of the economy 
are concerned, is independent of, and in the order of 
nature prior to, the brain and spinal marrow. 

218. In the human body, such a system is readily 
found. In the very midst of those parts which are 
known to be the first produced in the natural order 
of development (174), is a mass of nervous matter, 
which, in composition, very nearljjr resembles the 
brain. This mass, which may with propriety be 
considered as a species of brain, is undoubtedly the 
very first-formed portion of the human bodv, and is 
the grand centre which presides over all the ranctions 
concerned in the development and growth of the body, 
and the general function of nutrition, during life. 



219. In close connexion with this central mass, 
and scarcely second to it in order of time, is produced 
the rudiment of a heart, with a few of its principal 
blood-Tcssels, which gradually extend and enlarge 
and become more complex^ 'into all of these, as a 
part of their texture, enter branches from the central 
mass, which thenceforward through life, presides in a 
general manner over all the functions of the sangui- 
ferous system. Accompanying the blood.ressels, 
numerous other branches of nerves go out from the 
central brain, in different directions, and form other, 
smaller, and subordinate brains, which become 
the more special centres of development, and 
of perception and action, to individual organs, or par- 
ticular apparatuses of organs. These subordinate 
brains or special centres, in their turn, give off num- 
erous branches, some of which enter into the texture 
of the blood-vessels formed for, and appropriated to 
their service in the construction of their particular 
organs ; others are distributed to the contractile tis- 
sue or muscles of those organs, as the conductors of 
the stimulus of involuntary motion ; others also are 
distributed to the organs as the nerves of organic sen- 
sibility, or the conductors of impressions made upon 
the organs, to their special centres ; and finally, in 
order to establish a more intimate connexion between 
the different special centres, and bring them all into 
a more direct relation to each other, and to the com- 
mon centre, large cords run directly from one centre 
to another; and numerous branches go from each 
centre, to interlace and unite and form plexuses with 
branches coming from several other special centres, 
and from the great common centre. 

220. The alimentary canal and the other organs 
associated with it in the general function of nutrition, 
being earlier in the order of development than the 
other parts of the bodv (174), the special centres 
concerned in their development, and which are the 
more special centres of perception and action to them 
during life, are the first of the subordinate brains 
which the formative economy produces. At an early 
stage of the general development, however, numer- 
ous fibres rise on each side of the central mass, which 
form a pair of large cords, called the trisplanchnic 
nerves, that pass upwards, the one on the right and 
the other on the left side of the middle line, and give 
rise to an elongated mass or an uninterrupted series of 
small brains, which gradually separate in a longitudi- 
nal direction, and draw farther and farther apart, 
keeping up their connexion with each other by inter- 
mediate branches, till they form a connected range 
of about fifteen little brains, on each side, extending, 
in a fully developed body, along the spinal column 
from the bottom of the thoracic cavity to the top of 
the neck. In the progress of these developments, the 
trisplanchnic nerves become divided in their upper 
portions into from three to seven or more branches, 
which terminate in as many of the little brains in 
the two ranges. Eip^ht or nine more of these little 
brains are arranged m a similar manner, on each side 
in the abdominal cavity, so as to form, in the com- 
pletely developed body, a continued series, on each 
side of the back bone, from the base of the cranium 
to the inferior extremity of the spinal column. Each 
of these little brains in the two ranges, sends out nu- 
merous branches, some of which serve, as I have said, 
to unite the several little centres successively to each 
other : others plunge into the muscles : and others 
form connexions with the nerves and muscles of 
animal life, of which I shall speak hereafter. But 
ihe largest number of branches, from each of these 
little brains in the two ranges, go to interlace and form 
numerous plexuses with branches from others of 
the same, and of the opposite side, and from those 
more deeply seated amone the viscera, and from 
the great central mass itself. From these plexuses, 
again, numerous branches are given off to the dif- 

ferent orffans, entering intimately into their texture. 
And aU the branches and twigs of this system of nerves 
as they proceed along their course to their destination, 
cross and unite and divide and interlace* so as to foxm 
of the whole system, one extended net, the meshes of 
which become smaller and smaller, as the nerves be- 
come more and more attenuated and approach to their 
inconceivably minute termination in the organs. 

221. The two ranges of little brains, with their 
connecting cords and other branches which I have 
just described, are generally supposed by physiologists 
to be designed to brin^ all the parts associated in the 
functions of orgranic life, into a closer union, and to 
establish between them the most intimate and power, 
ful sympathy: and, therefore, they are commonly 
called the great sympathetic nerves. Some writers, 
however, include under this denomination, all the 
nerves of organic life. But I apprehend there has 
been much error of opinion on this point. What- 
ever may be the anatomical knowledge concerning 
these nerves, which they have derived from written 
descriptions, or from dissections, most writers on an- 
atomy and physiology still speak ^ the brain or spi- 
nal marrow as the grand centre^f nervous power, 
which presides, in a general manner, over all|the func 
tions of organic life, as well as those of animal or 
phrenic life ; and, therefore, they do not seem to per- 
ceive any other use for the nerves of organic life, than 
merely to serve the purposes of sympathetic associ- 

222. That the two series of little brains, with their 
connecting cords, etc., do serve to bring all the organs 
with which they are connected into a closer union 
as a single svstem, and to establish between them a 
more powerful bond of sympathy, is, I think, un- 
doubtedly true, and I consider it equally certain that 
theyperform other and very important offices. 

223. Considering this whole system of nerves as 
that which presides over all the vital functions in the 
development and sustenance of the body, and the other 
special centres already described, as being more 
immediately concerned in the development of the 
organs employed in the general function of nutrition, 
does it not legitimately follow from physiological an- 
alogy, as well as from anatomical arrangement, that 
the two series which extend the whole length of the 
spinal column, are more immediately concerned in the 
development of the spinal nerves, and of the cerebro- 
spinal system generally, and perhaps also of all the 
other parts pertaining to the trunk and extremities ? 

224. It seems to be a general law of the vital econ- 
omy, in the development of organized bodies, that, 
where any new subordinate centre of action is estab- 
lished for the construction of any particular organ 
or apparatus, a subordinate brain or nervous gangfion 
is produced. Every anatomist knows that one of 
these ganglions is found on each spinal nerve, near 
its connexion with the spinal marrow, and several 
of them are found in the brain; and, accord- 
ing to some, the spinal marrow itself is but a con- 
tinued series of them. Now then, if the spinal nerves 
are not developed from and by the spinal marrow, 
as the original centre of action in the formative pro- 
cess of the vital economy, but are developed indepen- 
dently of it, by frinctionsover which the nerves of or- 
ganic life preside (223), where does the development 
of these nerves commence, if not at the ganglions near 
the spinal marrow? — and is this not rendered still 
more probable by the fact, that each of these gan- 
glions is directly connected by large cords, with 
one of the little brains of organic life, whidi from 
the extended series along Uie two anterior sides of the 
spine, and one of which lies very near to each of 
the ganglions of the spinal nerves, with which it is 
connected ? There may be insuperable objections to 
this view of the subject, but if there are, I confess I 
have not yet been able to discern them. 



2S6. la brief review of this whole system of nerves, 
we perceive then, that, hj meant of oords which 
unite the several little brains to the great cen- 
tral mass, Mid those which unite the little brains 
to each oUier, and the numerous branches from the 
different centres, which interweave and form plexuses 
in every part of the two great cavities of the body, 
aU of theae centres are brought into the most intimate 
and powerful union, as a single nervous system ; and 
then, by means of the numerous branches distributed 
horn each of th^e centres to its particular organ or 
organs, and the numerous branches which pass from 
the several plexuses to different organs, the whole 
Miemblaffe of organs concerned in the functions of 
organic life, is, as it were, woven into one grand web 
of nervous tissue, and brought into a general and 
powerful communion of sympathy. 

S96. I have said (218) that in composition the cen- 
tral mass nearly resembles the proper animal brain. 
This is also true of all the special centres or subordi- 
nate brains. Like the proper animal brain, they are 
all composed of the white and the gray nervous sub- 
atance, surrounded by avascular membrane, analogous 
to the piamater of that organ (272), and an external 
o&velope of dense cellular tissue. They have the clos- 
eat resemblance to, and indeed seem to be but repeti- 
tions of, the brain of some of the lower animals ; and 
thev undoubtedly perform many of the functions of a 
brain, acting as centres to all necessary extent in their 
appropriate spheres, both in receiving impressions 
from, and in dispensing nervous powers to, their special 
domains. In the nomenclature of anatomy, however, 
Uiese bodies are termed ganglions or Icnots. The 
great central mass ivhich is situated at the roots of 
the diaphragm, in the upper and back part of the ab- 
dominal cavity, or nearly back of the pit of the stomach, 
consists of several parts. 1. Two semicircular bodies 
about an inch long and half an inch broad, lying one 
on the right, and the other on the left side of the 
backbone. These are called the semilunar 
0AKOLIOK8. They are, probably, at first, 
nnited in a single mass, and afterwards partially 
separated to accommodate themselves to the dupli- 
cate arrangement of the human body (281). They 
however remain closely connected by many large 
branches, which pass from one to the other, and form 
what is called the solar plexus. These two semi- 
lunar ganglions, united by the solar plexus, constitute 
the grand centre of all the ganglions and plexuses of 
organic life. Surrounding this great centre, as I have 
said (219), and united to it by cords and plexuses, are 
the numerous special centres which subordinately pre- 
side over particular functions. These, and the gang- 
lions that range along the two sides of the back bone, 
are much smaller than the semilunar ganglions, and 
are of an irregular ovate form. 

227* The ganglions of organic life are, in the de- 
scriptions of anatomy, divided into two orders, called 
the central and the peripheral or limiting ganglions. 
The central are those which are more deeply 
feated among the viscera, and which are supposed to 
preside generally, and specially, over the functions 
concern^ in nourishing and sustaining the body: 
the peripheral or limiting are those which form 
the two ranges on the sides of the spinal column, 
and have been supposed to be more particularly ap- 
propriated to the general sympathies of the internal 
system, and are accordingly called the sympathetic 
nerves (221). 

228. This general system of nerves, consisting of a 
common centre, and many special and subordinate 
centres, with their numerous cords, branches, plexu- 
ses, etc (226V is sometimes called the ganglionic sys- 
tem. And, because these nerves preside over all the 
Amotions common to animals and vegetables (208), 
and, in health, without the consciousness of the ani- 
mal, they are also called the nerves of vegetative life; 

but they are most commonly denominated the 
NERVES OF ORGANIC LIFE, in contra-distinctiou to 
the brain and spinal marrow with their branches, 
etc., which are called the nerves of animal life. 

229. There seems, however, to be little propriety in 
calling these latter the nerves of animal life, for they 
have no independent l{fe peculiar to themselves, nor 
are they directly and immediately concerned in main- 
taining the common life of the body. Their fiinctions 
may be entirely suspended for a considerable time, 
and still the common vitality of the body be preserved. 
Andrew Wallace, a surviving revolutionary veteran, 
now over a hundred years old,* and remarkably vig. 
orous and active, was struck down by lightning 
while tending a cannon on the fourth of July, soon 
after the close of the American Revolution, and lay 
seventeen days in a state of suspended consciousness 
or animation : and a youth now living in Philadelphia 
once lay twenty-eight days in this condition. But a 
single moment^s entire suspension of the functions of 
the nerves of organic life, would be a death from 
which there can be no recuscitation. The brain 
and spinal marrow with their nervous appendages are 
also sometimes called the phrentic nerves, as being the 
more immediate and exclusive organs and instruments 
of the mind ; but they are perhaps most commonly 
and most properly called the cerebro-spinal sys- 
tem OF nerves. 

230. Of the nerves of organic life, there are three 
orders (219). First, according to nature, those that 
enter into the texture of the blood-vessels, and other 
portions of the vascular system, and go with them in 
all their ramifications, to their most minute termina- 
tions in the different tissues, and preside over all their 
functions of absorption, circulation, secretion, structure, 
etc. ; second, those that go to the contractile tissue, or 
muscles of involuntary motion in the texture of the 
organs, and convey to them the stimulus of motion ; 
third, those that are distributed to the organs, as the 
nerves of organic sensation, and which convey to the 
special centres, and, if necessary, to the common cen- 
tre (226), the impressions made upon the organs. 
The cords which serve to connect the special centres 
to the common centre, and to each other, are proba- 
bly composed of filaments of all these three orders. 

231. In this distribution of the nerves of organic 
Ufe, each organ is supplied according to the nature of 
its function, and its relative importance in the system. 
The heart, which in its rudimental state, lies near 
the great ganglionic centre (219), and which, with its 
vessels, is first employed in constructing the alimen- 
tary canal and the organs associated with it in the 
general function of nutrition (220), is gradually re- 
moved farther and farther from the centre, as the 
several parts of the system become developed and en- 
larged. Composed of tissues peculiarly susceptible 
to the action of their appropriate stimuli, and simply 
employed under vital control, as a mechanical power, 
to circulate the blood, without effecting any changes 
in it, the heart seems to require and to possess but 
few nerves. All this is likewise true of the large 
blood-vessels. But in the capillary system, or minute 
extremities of the vessels, where all the important 
changes take place, the nerves much more largely 
abound. But as I shall have occasion to speak of the 
tissues of the several organs, when I come to treat of 
their functions, it is not necessary to enter into parti- 
cular details here. I will, therefore, at present, only 
observe that, of all the organs of the body, the sto- 
mach is the most remarkable for its nervous endow- 
ments, and for its functional and sympathetic rela- 
tions. Lving near the great ganglionic centre, it 
receives a large supply of nerves directly from that 
source, and is thereby brought into the closest sympa- 
thetic union with the common centre of organic life, 
and through it with all the organs and parts in its 

* Wallace has since died, at the age of 105 years. 



domain. By the arrangement and distributions of 
plexuses also, the stomach is brought into very direct 
relations with the heart, liver, lungs, and all the other 


232. I have already stated (214) that it has been 
a prevailing opinion among physiologists, that the 
spinal marrow is the grand nervous axis of original 
centre, from which spring all the other parts of the 
whole nervous system belonging to the human body, 
and that it, in a general manner, presides over all the 
formative processes in the organic development, and 
all the functions of the rivS. economy, during life. 
But we have seen (215) that these opinions cannot 
be true, because the brain and spinal marrow are 
among the last-formed portions of the body, and every 
other part of the body may be, and actually has been, 
completelv developed without them. 

233. The cerebro-spinal nerves, therefore, tog^ether 
with the muscles of voluntary motion, and the bones 
of the head, and upper and lower extremities, are 
purely and exclusively organs of external relation, 
and are, to no extent, directly and effectively concer. 
ned in the original formation and development of the 
body, nor in its permanent economy of nutrition and 
general sustenance ; nor are they in any manner or 
degree essential to the life of the body, until respi- 
ration and deglutition become necessary. The intro- 
duction of proper external substances into the lungs 
and stomach, and the voluntary evacuations of excre- 
mentitious matter, are the only immediate duties 
which they have to perform, and the only direct agen- 
cy which they have to exercise, in all the complicated 
processes of the general function of nutrition. 

234. The nerves of organic life then, presiding wholly 
and exclusively over all the formative processes of 
organic development, and the cerebro-spinal system 
being as purely and entirely passive in those processes 
as the cartilages and ligaments, it necessarilv follows 
that the organic system is not developed either from 
the brain or spinal marrow, as the original centre of 
development and point of unity to the formative econo- 
my, but the several parts may be, and in fact are, 
originally formed in a measure independently of 
each other, having at first no other connexion than 
that which is formed by the nerves of organic life 
(230), and by the common system of blood-vessels by 
which they are all constructed. As the development 
of the separate parts progresses, they become more and 
more nearly associated, and finally become closely 
and permanently connected, forming of the whole as- 
semblage a single system of organs, and establishing 
by their combined functions, a single vital economy, 
by which the individual is sustained and the species 

235. The cerebro-spinal nerves, therefore, instead 
of springing from the brain, or spinal marrow, or any 
other common centre, originate with the parts to which 
they belong, and in the progress of the general devel- 
opment, become permanently connected with the spi • 
nal and cerebral centres. Some modern physiologists 
indeed, contend that the nerves of organic life, as well 
as those of the cerebro-spinal system, originate in the 
extremities of the parts of which they belong, and ter- 
minate in the centre, and that the formative pro- 
cess by which organic bodies are developed, are, both 
in vegetables and animals, effected by a species of vi- 
tal force, which does not depend on any nervous sys- 
tem ; and consequently that the several parts of the 
body with all their tissues may be, and probably are, 
originally formed without any connexion with each 
other, as so many distinct individual beings ; and, in 
the progress of development, become united in a sin- 
gle system. But this is both contrary to fact and to 
every sound physiological principle and analogy. 
Whether vegetables have nerves or not, we know 

that the economy by which they are developed has a 
puncium saltenSf a single starting point; and that, 
in all its processes, this is the grand point of unity, 
the general centre of action : and we know with equal 
certainty that this is also true, in the development 
of animal bodies. A grand centre of unit^ and of 
action is first established, and this is maintained with 
strictest integrity throughout the whole progress of 
development. This centre, I have said (226), is the 
central brain of the nerves of organic life, consisting, 
in the fully developed body, of the semilunar ganglions 
and solar plexus ; and from this common centre, all 
the subordinate centres with their connecting cords, 
branches, etc., are developed, by the blood-vessels over 
which these nerves preside (219), and which in all 
stages of the general development, have also a com- 
mon centre or heart, from which they all receive 
their blood. There must, of necessity, therefore, be 
an entire unity in the formative economy by which 
animal bodies are developed, so far as the nerves of 
organic life and the blood-vessels are considered. But 
different portions of these, acting by special centres, 
in a subordinate manner, as I have already described 
(219), may, and in fact do, commence at different 
points, the structure of different parts, in a measure 
independent of each other (174), just as ossification 
commences simultaneously at many different points, 
which have no immediate connexion with, nor depen- 
dence upon, each other, while at the same time they 
all depend upon a single economy, acting from a com- 
mon centre. In this manner, the cerebro-spinal 
nerves, instead of being developed in unity from a com- 
mon centre, originate in several parts, and by subse- 
quent connexion, constitute a single system. Hence, 
as we have seen (215), the spinal nerves may be de- 
veloped without a spinal marrow, and, as is frequently 
the case, the spinal nerves and marrow may be devel- 
oped without a brain ; and we are told that there 
have been instances in which the brain has been devel- 
oped without a spinal marrow. 

236. The natural order of development in the cere- 
bro-spinal system of nerves, in the human body, is 
probably as follows : 1. The spinal nerves, or those 
which are commonly described as arising from the 
spinal marrow. The development of these, as I have said 
(224), probably commences at the ganglions near the 
spine (Fig. 14, d), 2. The spinal marrow itself. 3. 
Those ganglions of the brain, which are common to 
the lower orders of the vertebrated animals, and 
which are essential to the functions of taste, smell, 
hearing, and sight, together with the special nerves by 
which these functions are performed. ' 4. The gang- 
lions which more particularly belong to those portions 
of the brain which constitute the more immediate and 
special organism of the mental and moral faculties ; and 
5. The cerebral hemispheres themselves. I do not mean 
to be understood, however, that each preceding part 
is fully developed before the succeeding one is com- 
menced; but that the natural order in which the de- 
velopment of these severid parts commences, is such as 
I have described. 

237. Having thus nointed out the natural order of 
development, x shall now proceed to a more particu- 
lar description of the several parts of the cerebro- 
spinal system' of nerves ; not in the order in which 
they are developed, but as they present themselves to 
the eye of the anatomist in the dissection of the dead 
body; becauto this is the usual manner of describing 
them, and therefore will probably be more readily un- 

238. The spinal marrow is that soft substance which 
lies in the hollow of the back bone (180, 182). To a 
careless observer, it appears to be a common mass of 
marrow ; but when carefully and properly examined, 
it is found to be composed of the white and the gray 
nervous substances (161); the gray being situated in- 
ternally, somewhat like a series of ganglions, and sor- 



nmnded by the white. It is natnnJly dirided, longi- 
tadinally, into a right and left half : each of which 
conristi of a front and back oolumn, so that the 
whole marrow is composed of four columns, or rather 
of two corresponding pairs ; as the two front portions 
eorrespond with each other in form and character ; 
and the two back portions correspond with each other 
in like manner; thus constituting a double spinal 
marrow, as if the two halves of the body had a dis- 
tinct and independent existence; which, indeed, so 
far as the spinal marrow and its nerves are concerned, 
is really the case. For, as we shall see, the whole of 
one side may be paralyzed while the other remains in 
the full possession of its powers. 

239. The spinal marrow is enveloped in three differ- 
ent membranes. The first, which everywhere closely 
adheres to it, is full of blood-vessels that are supposed 
to nourish it, and hence the membrane is called the 
piamater^ or natural mother. The second, called the 
arachnoid, or spider's-web membrane, is extremely 
thin, and is continually moistened by its own serous 
ezhiilation. The third, or external one, which may 
properly be considered the lining membrane of the bony 
cavity or canal, is a strong fibrous membrane, like 
that which everywhere surrounds the bones: and 
some anatomists think this a continuation of the pe- 
riostium. It is here, however, called the duratnaier, 
or hard mother. These membranes are all thiee 
composed of the cellular tissue (169). 

240. Connected with the spinal marrow, through 
small intervertebral openings formed for the purpose, 
on each side of the spinal canal, are thirty pairs of 
nerves, which are called the spinal nerves. Each of 
these nerves consists of numerous filaments, surround- 
ed by the pta-ma/er, and an external envelope of 
strong cellular membrane, resembling the dura-mater, 
and which some anatomists consider a continuation 
of the dura-mater ; but others are of a differen opin- 

241. As the cerebro-spinal nerves on each side of 
the middle line, or in each half of the body, are pre- 
cisely alike, it is most convenient to describe them on 
one side only. I shall therefore adopt this method, 
and I wish it to be understood that when I speak of 
a single nerve, it is one of a pair, the corresponding 
one being on the opposite side. 

242. According to Sir Charles Bell, Magendie, and 
others, a part of the filaments which compose each 
spinal nerve, rise from [or terminate in] the back 
portion, and a part from the front portion of the spi- 
nal marrow (Fig. 14). Those which rise from 

Pig. 14. 

A seetion of tht apinal marrow, showing the c 
it and the spinal nenres by double roots, 
a, spinal marrow. 

6, root of spinal nerre from bade portion, 
e, rot t from front portion. 
d, ganglion on the posterior p^rt 
t, &e two parts united in one eol^L 


m mm 

the back portion (6), almost immediately run into 
a ganglion (</), and proceeding from this, they unite 
with those that come from the front portion (c), and 
form the cord {e) which goes out to be dispersed over 
the body. But in entering into the formation of the 
cord, the filaments retain their filamentary form and 
original character, and are again, ultimately, separa- 
ted. The filaments which rise from [or terminate in] 
the back portion of the spinal marrow, are the nerves 
of animal sensation. Some £ew of these are distribu- 
ted to the muscles of voluntary motion, and endow 
those organs with a small degree of animal sensibility, 
by whiph the mind is informed of the action of the 
muscles in obedience to the will, and enabled to regu- 
late the extent of the action. The rest of the posterior 
filaments proceed to the outer skin of the body, and 
b^ endowing it with a high degree of animal sensi- 
bility, constitute it a general organ of touch, which is 
the fundamental animal faculty of external relation. 
They however abound more in some parts than in 
others, making particular portions of the body the 
more special organs of touch. In m an, the ends of the 
fingers are pre-eminently qualified for this function. 

243. The filaments which arise from [or terminate 
in] the front portion of the spinal marrow, are the 
nerves of motion. They are all distributed to the 
muscles of voluntary motion (194), ramifying in great 
numbers over the whole of this part of the muscular 
system, and penetrating to the smallest muscular fila- 
ments. These convey the stimulus or influence of the 
WILL, to the voluntary muscles, causing them to con- 
tract in obedience to the will, in the performance of 
voluntary motions. If, therefore, the filaments from 
the back portion of the spinal marrow be separated 
from that centre, the animal sensibility of the parts 
to which they are distributed is immediately destroy- 
ed, or in other words, the animal centre of perception 
has no longer cognizance of any sensations or affec- 
tions in those parts ; yet the power of voluntary motion 
will remain. But if the filamentafrom the front por. 
tlon of the spinal marrow be separated from that 
centre, the power of voluntary motion of the parts to 
which they are distributed will be lost, while the 
sensibility will remain. 


244. The same column of nervous matter which, in 
the hollow of the back- bone, is called the spinal mar- 
row, continues upward, and passing through a large 
foramen or opening in the base of the skull, extends 
about an inch into the cranium (Fig. T, g). Near its 
entrance into the skull, according to Meckel and 
others, its two lateral parts divide into several fasci- 
culi or cords, which cross obliquely, so that those 
from the right side take the left, and those from the 
left take the right : and, at the same time, they are 
enlarged bv the addition of masses of gray substance 
(161V Tie head of the spinal marrow is now divi- 
ded into six parts, or three pairs of bodies (fig. Ifi, 
m): two corresponding ones in front (h), called the 
PYSAMiDAL BODIES ; two Corresponding ones behind, 
called the restifobm bodies ; and two corresponding 
ones at the sides (t), called the olivary bodies. These 
last are principally composed of the gray substance, 
surrounded by a thin layer of the white. Besides 
the parts which I have described, there is, according 
to Sir Charles Bell, a convex strip of medullary mat- 
ter lying between the restiform and olivary bodies, 
and extending down between the anterior and poste- 
rior portions of the spinal marrow (238), which gives 
origin to the several nerves particularly associated in 
the function of respiration. These three or four pairs 
of bodies are so united as to form a single bulb, about 
one inch in length and about two thirds of an inch in 
diameter, and commonly called the Medulla Oblongata 
(Fig. 16, m). ^ 

245. From the sides of this bulb, rise several pain 



of nenres, and from its top all the other parts within 
the cranium^ which I will briefly describe in order 
from below upwards. 

In the region of the neck, a number of branches 
and fllaments from several different nerves, unite to 
form a nerve which descends to the diaphragm, and is 
<ymcerned in the function of respiration. In its course 
from its origin to its termination, it gives off twigs 
which go to different parts, and unite with twigs from 
the ganglionic nerves of the neck, with branches from 
the solar plexus, and with other important nerves. 
This nerve belongs to that portion of the respiratory 
apparatus, which ordinarily acts without the agency 
of the WILL, but which the will can act directly upon, 
and, to a limited extent, control. The next nerve 
above, called the spinal accessory> has an extended 
origin. Some of its roots arise from the lower part 
of the marrow of the neck, others from the middle, 
and others from the upper part of the same region. 
These all enter the skull with the spinal marrow, and 
after receiving three or four roots from the medulla 
oblongata, unite to form a cord which passes out at a 
imall opening in the base of the skull, and is distri- 
buted to the muscles of the neck concerned in moving 
the breast and collar bones and shoulder blade, and 
in drawing back the head and shoulders. This is one 
of Sir Charles Bellas respiratory nerves ; and according 
to that distinguished anatomist, both this and the 
diaphragmatic nerve spring from the middle strip of 
medullary matter, which I have named. Of those 
nerves which have their origin entirely within the 
skull, the lowest is called the hypoglossal. It arises by 
a series of roots, from the groove between the pyram- 
idal and olivary bodies, and passes out at another small 
aperture in the base of the skull, and after giving off 
twigs in several directions, and receiving twigs from 
other nerves, it divides into many branches which 
are distributed to the muscles of the tongue, imparting 
to them the power of voluntary motion in mastication, 
swallowing, speaking, singing, etc. The nerve next 
in order above, is called thr pneumo-gastric, or the 
lungs-and-stomach nerve. It arises by numerous roots 
very near the top of the medulla oblongata, and ac- 
cording to Sir Charles Bell, from the respiratory strip 
between the restiform and olivary bodies. It issues 
from the skull with the spinal accessory : and by nu- 
merous branches and twigs, forms connexions and 
plexuses with almost every nerve in the region of the 
throat and neck and thoracic cavity, to such an ex- 
tent, that it h^as been called the middle sympathetic. 
It sends branches to the pharynx, or top of the meat- 
pipe, and to the meatpipe itself, to the larynx or organ 
of voice at the top of the windpipe, and to the wind- 
pipe in all its branches and whole extent. It also 
sends branches which unite with others from the cer- 
vical ganglions of the sympathetic, to form what is 
called the cardiac plexus, and at the bottom of the 
neck it sends back a recurrent branch to the larynx 
and windpipe and other adjacent parts : and these dif- 
ferent branches interweave and unite in every direc- 
tion, so as to bring the organs of the throat and neck 
into very direct and important relations. Several 
branches of this nerve also enter into the formation 
of plexuses for the lun^s : and some twigs extend to 
the solar plexus, to the plexus of the liver, spleen, etc. ; 
but the main body of this nerve descends to the 
stomach, and is distributed over that or^an, inter, 
weaving and uniting extensively with the nerves 
which come from the solar plexus, the great centre of 
organic life. 

246. This nerve has been the subject of more specu- 
lation and experiment and discussion and controversy 
among physiologists, than perhaps any other portion 
of the human system. Some, as I have stated, have 
oonsidered it the middle sympathetic nerve, the office 
of which is to maintain a direct sympathy between 
all the parts to which it bebngs, and especially be- 

tween the brain and the stomach. Some have sup- 
posed that it is simply the medium by which the want 
of air in the lungs and of food in the stomach is com- 
municated to the animal centre of perception and ac- 
tion ; others, that it conveys to the lungs and stom- 
ach the nervous energy by which those organs are 
enabled to digest the inspired air and the ingested 
food. Some have considered it an animal nerve, and 
others a vegetative nerve. Some have thought it 
wholly a nerve of sensation, and others that it is 
both a nerve of sensation and motion ; and others 
again contend that it is exclusively a nerve of 
motion. It has been tied and cut and experimented 
on in various ways, and with various results in 
the minds of the experimenters, according to their 
particular theories. Some assert that if it be cut or 
tied, digestion, respiration, and the action of the heart, 
are entirely arrested ; while others contend that 
digestion is' only temporarily interrupted, and respira- 
tion is arrested only by the closing of the top of the wind- 
pipe, and that the action of the heart may be restored 
by artificial respiration. But in all these experiments 
the sympathies of the system seem to have been wholly 
overlooked (206, 216). Sir Charles Bell tells us that it 
is exclusively a respiratory nerve, and that it imme- 
diately* or remotely associates all the parts to which 
it is distributed, in the function of respiration. 

247. Amidbt such a wilderness of discrepant opin- 
ions and statements, it is impossible to decide from 
their authority where the truth lies ; but there are 
several important considerations which should ever 
be kept in view, when we attempt to arrive at a con- 
clusion on this vexed question. In the first place, 
this is a large nerve issuing from the very top of the 
medulla oblongata, a point towards which all other 
parts in the body, below and in the skull above, seem 
to converge. In the second place, it not only anasto- 
moses, or forms connexions, by numerous branches, 
with several other nerves Issuing from the cranium, 
but also anastomoses freely, and even from plexuses 
with the nerves of organic life, from the cervicle and 
and thoracic ganglions of the sympathetic. In the 
third place, the main body of the nerve proceeds very 
directly to, and expends itself upon, the stomach, as 
if that organ wereits grand point of destination, and all 
its other distributions secondary or of less importance. 
It is said to send some branches to the heart, but all 
those branches are first merged in plexuses with nerves 
of organic life, and few if any of them reach the heart, 
even in a modified form. Those branches which go 
to the substance of the lungs are also much involved 
in anastomoses and plexuses, and perhaps considera- 
bly modified by other nerves, before they reach their 
destination. In the fourth place, some filaments of 
this nerve extend to the great centre of organic life, 
or solar plexus (226), and the plexuses immediately 
formed from it and surrounding it. Would this be 
the case if it were simply a motor nerve ? In the 
fifth place, it is pretty certain that those branches of 
this nerve which are distributed to the pharynx and 
larynx and the muscular portion of the windpipe, are 
nerves of voluntary motion ; and that the section or 
paralysis of them destroys the vocal power and the 
power of deglutition or swallowing : and it is entirely 
certain that the will has no direct control over that 
large portio4 of this nerve which is distributed to the 
stomach ; nor is there the least reason to suppose it 
has over those branches which reach the substance of 
the lungs. Moreover, it is very certain that in the 
stomach the pneumogastric is not a nerve of common 
animal sensibility of feeling, while its branches in the 
lining membrane of the larynx and windpipe appear 
to be highly sensible. Finally, the special sense of 
hunger and of thirst, and the well known direct and 
powerful svmpathy that exists between the brain and 
the stomacn, seem to require the agency which has long 
been attributed to this nerve. Indeed, it appears to 



occupy a middle ffround between the nerves of or- 
gMiic and animal fife ; and, if such a things may be, 
1 am inclined to think that, in its origin, it is an ani- 
mal nerve of sensation and motion, and after forming 
its ereat plexus^ and becoming intimately associated 
wiia the nerves of organic life, it becomes an animo- 
organic nerve of the same powers, giving motion per- 
]uu»8 to the bronchsB and certain motions to the stom- 
ach, which take place in vomiting, etc., and constitu- 
ting the medium by which the centre of animal per. 
ception has cognizance of those wants of the organic 
domain which are indicated by hunger, thirst, and the 
desire for air ; and by which, also, the brain and the 
stomach, and other parts associated by this nerve, are 
brought into more direct and powerful sympathy with 
each other. Something verv analogous to this 
is found in the trifacial nerve, if it be true that that 
nerve endows the tongue with gustatory power. But 
whatever the pneumogastric nerve may have to do 
with the motions, sensibilities, and sympathies of the 
stomach and lungs, the general law of physiological 
analogy teaches us that it is not directly and imme- 
diately concerned in the important changes which take 
place in them, these depending entirely on the vital 
properties and functional powers of the nerves of or- 
ganic life, connected with the capillary vessels of those 
organs (230). 

248. The next nerve in order is called the gloso- 
pharangeal, or tongue-and-pharynx nerve. It rises 
by numerous filaments from the groove between the 
restiform and olivary bodies, immediately above or 
before the pneumogastric, and passes out of the cra- 
nium with the latter nerve. Indeed, some anatomists 
think it actually forms a part of the pneumogastric. 
Sir Charles Bell classes it among his respiratory nerves. 
On its exit from the skull, it gives off several branches, 
which unite with other nerves, and supply many parts 
in the region of the throat ; but it is mainly distribu- 
ted to the pharynx and tongue. According to Sir 
Charles, it gives motion to the muscles of the tongue 
and pharynx, and more especially those necessary for 
the articulation of the voice. Spurzheim, on the con- 
trary, says : * This nerve appears to be destined to gen- 
eral sensation or feeling.' Another nerve rises imme- 
diately above and on the same line with the one just 
described, which is called the facial nerve. It passes 
out at an opening near the ear, and is principally 
distributed to the muscles of the face ; being disper- 
sed over the chin, lips, angles of the mouth, cheeks, 
nostrils, eyelids, eyebrows, forehead, ears, neck, etc., 
and uniting in its ramifications with the branches 
and twi^ of several other nerves. This is another 
of Sir Charles BelPs respiratorv nerves ; and, ac- 
cording to him, it is the principal muscular or motor 
nerve of the face, and orders all those actions which 
are,, in any degree, connected with the acts of respi- 
ration ; and on it the expressions of the face depend. 
The next nerve is called the abductor, or the external 
muscular nerve of the eye. It rises from the top of 
the pyramidal body, and passes out at an opening in 
the back part of the cavity formed for the eyeball, and 
goes to the muscles which turn the eye outward. 
This nerve is entirely appropriated to voluntary mo- 
tion (Fig. 15, No. 6). There are six other pair of 
nerves, including those of special sense, which origi- 
nate within the cranium, and all of which actually 
rise, either directly or indirectly, from the top of the 
medulla oblongata ; but their roots are so covered by 
other parts, or they originate in a manner so diffuse 
and indistinct, that they have the appearance of 
springinjf from ^arts removed from that point. 

249. In describing the remaining nerves, I shall 
deviate from the usual order, and proceed in a method 
of my own, £ot the sake of placing important points 
in the strongest light with reference to physiological 
relations. The nerve which next prcsento itself as 
we proceed forwards, is the auditory (fig. 15, No. 8), 

and the next is the trifacial (fig. 15, No. 5), both of 
which I shall leave for the present, and pass to the 
two remaining muscular nerves of die eye. The in- 
ternal motor nerve of the eye is the smallest that 
originates within the cranium (Fig. 15, No. 4). It it 
the highest of Sir Charles Bell's respiratory nerves, 
and, according to that gentlemen, it rises from the 
very top of the medullary strip which gives origin to 
all of the nerves of the respiratory apparatus (244), 
and which terminates upwards and forwards, jutt 
under the masses called the corpora quadrigeminL 
This nerve passes out of the skull, with the nerve 
last described, and goes to the superior oblique mus- 
cle of the eye, which rolls the eye, and turns the pu- 
pil downward and outward, and gives the pathetic 
expression to the eye, and hence this nerve is called 
the pathetic. The common motor nerve of the eye 
(fig. 15, No. 3), rises by numerous filaments, which 
may be traced back nearly to the top of the medulla 
oblongata, and are then lost in parts coming from 
that point. The filaments soon unite and form Uie 
nerve, which passes out at the same opening with 
the two last described nerves, and is distributed to 
the greater number of the muscles of the eye, which 
serve to direct the pupil towards the object of vision. 

250. The nerves which remain to be described are 
those of special sense, and the trifacial. All these 
have their origin at or near the focal point, at the 
head of the medulla oblongata, from which all the 
parts within the cranium rise and diverge. This, it 
must be remembered, however, is according to the 
usual mode of anatomical description, rather than ac- 
cording to the natural order of development. It is 
highly probable, if not certain, as I have said (236), 
that tne parts within the skull do not actually sprint 
from the medulla oblongata, but that the cerebral 
ganglions, such as the quadrigeminal, the ophthalmic, 
and the striated bodies, are first formed or commenced 
in regular order of succession, and in due time united 
with the medulla obloneata and with each other by 
medullary fibres, and that from these are developed 
the parts more particularly connected with them. 
The quadrigeminal bodies are four small ganglions 
lying at the top of the medulla oblongata. A little 
removed from these are the two largest ganglions of 
the brain, called by the old anatomists the optic thai- 
ami, being supposed to give rise to the optic nerves ; 
and still a little removed from these last are two 
smaller ganglions, called the siriated bodies. All of 
these bodies are principally composed of the gray sub- 
stance (161), surrounded and traversed by uie white 
or medullary fibres ; and all lie near the centre and 
base of the brain, and occupy but a small portion of 
the cranial cavity. 

251. Anatomists have attempted to demonstrate 
the precise points at which the olfactory, optic, and 
auditory nerves rise from these bodies ; but no one 
has yet been so successful as to place the matter entire- 
ly beyond dispute. As these nerves are traced back- 
ward and inward towards Uieir origin, they become 
less and less distinct, and more and more indefinite, 
till they fade into the substance of the parts from 
which tney rise, and evade pursuit ; and this is parti- 
cularly the case with the optic and olfactory nerves. 
Indeed, all these nerves appear to have a general rehu 
tion to all the parts rising from, or terminating in, 
the common centre of animal perception and voluntarjr 
action, at the top of the medulla oblongata. 

252. The auditory nerves ^fig. 15, No. 8), are en- 
dowed with the power of receiving those impressions 
which we call sounds, and are distributed to the inner 
cavities of the ear as the special nerves of hearing. 
The olfactory nerves are endowed with the power of 
receiving those impressions which we call imelL They 
proceed forwards, and before they make their exit from 
the skull, they are considerably enlarged by a quan- 
tity of the gray substance (Fig. 15, No. 1). They then 



pass out through a number of small apertures, and 
. are distributed over the cavities of the nose, forming 
the external organ of smell. The optic nerves pro- 
ceed fowards a short distance from their origin, and 
then come together and form a junction, and again im- 
mediately separate, and continue forwards, and make 
their exit from the skull through the optic foramen ; 
and having passed through the outer coats of the eye- 
balls, they finally terminate in a delicate expansion, 
called the retina, which surrounds the humors of the 
eye (Fig. 15, No. 2). The nature of the union which 
these nerves form at their junction, is yet a matter of 
uncertainty. Anatomists and physiologists not only 
disagree on the subject, but in their argruments and 
in their statements of facts, directly contradict each 
other. Some assert that the two nerves cross each 
other entirely, so that the nerve which rises on the 
right side goes to the left eye, and that which rises on 
the left side goes to the right eye. These support their 
opinion by an arra^ of pathological and other facts 
and reasonings, which are very convincing and con- 
clusive. But others assert that there is only a junc- 
tion and no crossing of the nerves, and that even the 
Ainction is not essential to their functional powers. 
These again, by facts and reasonings, make out their 
case as clearly and as conclusively as those of the 
former opinion ; while yet others contend that there 
is a partial decussation, and establish their position 
most conclusively by facts and reasonings ; and stiU 
others, with equal force of facts and argruments, prove 
that there is no decussation, but an intimate and es- 
sential union of the substance of the nerves. From 
such contradictory statements, it is impossible to know 
what is true : but we have the satisfaction of knowing 
that whatever be true in the case, it is of little impor- 
tance to physiology. The optic nerve is endowed 
with the power of receiving those impressions which 
we call sight. It is the special nerve of vision, and 
is always present where the faculty of vision exists. 

253. The peculiar endowments of the nerves of 
special sense are generally considered as modifications 
of common animal sensibility ; but there is some rea- 
son to doubt the correctness of this opinion. It is 
certain that these nerves, at least in a healthy stete, 
have no tactile sensibility. The optic nerve is no 
more sensible to a puncture or laceration, than a dead 
tree, but it is most delicately sensible to light, which 
we can in no other possible manner appreciate nor 
perceive. Nor is there the least foundation for the 
notion which some have advanced, that other nerves 
may in some degree vicariously perform the functions 
of these nerves, in their absence. Indeed, the sense 
of touch is in all respects as truly a special sense as 
that of sight, hearing, smell, or taste. It is much 
more extensive in its special organism than any other 
sense, only because the relations of the animal to the 
tangible properties of things require that it should 
be so ; but the extensiveness of its organism does not 
in any measure render the sense less specific If the 
optic nerve instead of being expanded into the retina 
of the eyeball, were expanded like the skin over the 
whole external surface of the body, so that the ani- 
mal could see, as he can feel, at every point/ Uie optic 
tense would be no less a special sense than it now is ; 
because the speciality of a sense does not consist in 
the limitedness of its peculiar organism, but in the 
^cificness of its power. The sense of sight is a spe- 
dal sense, not because we can only see with the eye, 
but because^ we can only perceive special properties of 
external things by it, which we call the visual pro- 
perties of things ; and so of all the other senses called 
special. But the sense of touch is as specific in its 
power as either of the other senses, for by it we can 
only perceive the tangible properties of things, and 
therefi)re it is the special sense of touch, notwith- 
standing the faculty pervades the whole body. 

264. I now return to the trifacial nerve, or the 

fifth of the old anatomists. This is the largest nerve 
within the cranium, and in many respects corres- 
ponds with the spinal nerves. Like them it rises by 
two roots, has a ganglion, and is both a nerve of sen- 
sation and motion (Fig. 15, No. 5). In birds and 
other animals which have no annular protuberance, 
this nerve is plainly seen rising from the pyramidal 
and restiform bodies of the medulla oblongata ; but 
in man and other animals which have a large annular 
protuberance, the origin of the nerve is not so easily 
perceived. The posterior root of this nerve, coming 
from the restiform body, is much the larger, and is 
composed of thirty or forty fasciculi of different sizes, 
containing in aU about a hundred filaments, which 
interlace freely as they proceed forward to form the 
semicircular prominence or enlargement called the 
gasserian ganglion. This portion of the nerve is en- 
dowed with animal sensibility. The anterior portion 
which arises from the pvramidal body does not enter 
the ganglion. This is the motor portion of the nerve, 
and is ultimately distributed to those muscles of the 
face, concerned in mastication, etc. From the gas- 
serian ganglion the nerve proceeds in three large 
branches, called the ophthalmic, the superior maxil- 
lary, and the inferior maxillary. The ophthalmic is 
principally distributed to the eye, giving sensibility 
to the surface of the ball and the parts that surround 
it, sending some twigs to the nose, etc The superior 
maxillary is distributed to the upper part of Uie face, 
upper jaw, roof of the mouth, superior salivary glands, 
gum, lip, etc, sending a twig to each root of &Lch. 
tooth (Fig. 20), and ramifying generally over all the 
parts connected with the upper jaw ; some twigs ex- 
tending to the cavities of Uie nose, and interlacing 
with twigs of the olfactory. The inferior maxillary 
is distributed to the lower parts of the face, mouth, 
and region of the ear, supplying the teeth, jaw, gum, 
inferior salivary glands, tongue, lips, chin, etc ; and 
some of its twigs extend to the internal auditory ap- 
paratus of the ear. The inferior maxillary also gives 
rise to the branch which, after peculiar modifications, 
is endowed with the power of receiving those impres- 
sions which we caU taste, and is distributed by mi- 
nute filaments to the mucous membrane of the mouth 
and throat, and particularly upon the edges and tip of 
the tongue, and thus forming the special organ of 
taste.* In short, the trifaci^ nerve is distributed 
to every part of the face, forehead, eyelids, nose, lips, 
jaws, and ears ; and, in its extensive ramifications, it 
anastomoses or unites freely with the facial nerve, 
with several other nerves of the head, and with a 
g^eat number of twigrs from the sympathetic of or- 
ganic life. It communicates with the orgrans of all 
the five senses, and of voluntary motion, and brings 
these and all other parts to which it is distributed 
into general relationsnip ; and it also brings all these 
parts into a more direct and powerful rehtion with 
the stomach and the whole domain of organic life. 
This Is the universal nerve of sensation to the head 
and face, to the skin, to the surface of the eye, to the 
cavities of the nose, mouth, tong^ue, etc 

255. The trifacial nerve has been the subject of 
much physiological research, experiment, and specu- 
lation. It has, by some, been called the sympaUietic 
of the head ; and there certainly are many interest- 
ing analogies between this nerve, the pneumogastric, 
and the sympathetic of organic life (227). Tiede- 
mann, however, conceives that this last nerve is suf- 
ficient to answer all the sympathetic purposes of the 
body ; and as a medium of general sympathy it un- 
doubtedly is. Yet both the trifacial and the pneumo- 
gastric may act in their spheres as special sympathe- 

* There it lome queetlon whether the inferior maxillsry braaeh 
of the trifacial, does actually ftimish the gustatory nerre. Many 
experiments have been made on living animals, to settle this 
point: but the parts are so complicated, and different nerves art 
■o closely associated, that nothing perfectly satisfactory and coa- 
elofive has yet been ascertained. 



tics, bringing into more special and immediate rela- 
tionship particular parts, which are collectiTel)r em- 
braced by the great sympathetic, without at all inter- 
fering with the functions of this last nenre. In a 
state of extended inflammation, or a high degree of 
morbid sensibility, the trifacial nerve is certainly the 
medium of morbid sympathy between different parts 
to which it is distributed. The protracted irritation 
of the nenre of a decayed tooth, often gives rise to ear- 
ache, head-ache, etc. ; and sometimes these sympa- 
thetic symptoms continue constantly for years, or 
until the tooth is extracted. And we know, too, that 
those parts to which the trifacial is distributed as the 
principal nerve, sympathize very powerfully with the 
stomach, especially m a diseased state ; as the eyes, 
ears, teeth, etc. In that distressing complaint called 
sick head-ache, it is probable that both the trifacial 
and the pneumogastric nerves are much concerned. 

256. Such is the importance of this nerve to those 
of special sense, that some physiologists have supposed 
it inunediately essential to their ^nctional powers ; 
and some have even asserted that the functions of 
sight and smell are performed in certain animals by 
the branches of this nerve, in the absence of the optic 
and olfactory. But, most unquestionably, these 
opinions are erroneous. Yet it is entirely certain 
that the division of those branches which go to the 
eye and nose, will instantly destroy the sensibility of 
the parts, and soon cause a total abolition of sight and 
smell ; and all injury done to these branches com- 
mensurately impairs the functional powers of the 
optic and olfactory nerves : so intimately connected 
and reciprocally dependent are the several parts 
which compose a single organ and a whole system. 

257. There is one other view presented by some 
physiologists, of the trifacial nerve, which is exceed- 
ingly interesting and plausible. It is, that this nerve 
is peculiarly the cerebral organ of animal instinct. 
It is said that in the vertebrated animals, the devel- 
opment of instinct appears to be in a direct ratio with 
the trifacial, and that in those articulated animals 
whose brain corresponds with the gasserian g^glion 
of the trifacial nerve, the instinctive powers are more 
developed than in the members of other classes. 

258. The originators and advocates of this opinion 
affirm that the brain and trifacial nerve are always 
developed in an inverse ratio, and tnat the develop- 
ment of the trifacial and the instinctive faculties 
always bear a precise relation to each other. ' Man,* 
say they, 'is governed by reason, and not by in- 
stinct ; and in him the trifacial nerve, in comparison 
with the other parts of the nervous system, is reduced 
to its minimum of existence. The monkey, the dog, 
the elephant, and most of the higher mammalia, 
though immeasurably below man, appear to be di- 
rected by a kind of brute reason. In these a n imals, 
also, the trifacial bears but an inconsiderable proper- 
tion to the general nervous mass ; the instinctive 
£sculties are indeed manifest, but not carried to the 
extent they are met with in many of the lower orders. 
In the seal and beaver, among the manmialia, these 
faculties are at their highest pitch of development, 
and seem rather to be the effect of an unerring rea- 
soning power, than the result of the organization of 
instinct. In these animals the brain is reduced to a 
state of atrophy, whilst the trifacial is carried to an 
enormous extent of development. In the wasp, the 
bee, and the spider, and especially in the bee, instinct 
is carried to its highest perfection. And here the 
brain is wholly wanting; the gasserian ganglion 
being the predominating part of Uie nervous system 
in au the mvertebrata, and in the bee this organ is 
carried to its highest point of complexity and organ- 

259. All the parts of the nervous system which I 
have described may be developed, and all the func- 
tions immediately essential to animal and organic life 

may be performed, without the brain. ^ Many in- 
stances are on record of human beings, which were 
entirely destitute of the proper brain, and in which 
the two gasserian ganglions approached each other 
and became confounded in one general mass ; and with 
this, the olfactory, optic, auditory, and other nerves of 
the head, were connected, and during the life of the in- 
dividuals the functions of smell, vision, hearing, and 
taste, were perfect.' But these are monstrosities of 
nature, and fortunately are of rare occurrence. They, 
however, serve to demonstrate the relations and de- 
pendencies of parts ; and sometimes teach us impor- 
tant physiological truths, which it would be difficult, 
if possible, for us to ascertain in any other way. 

260. We see, therefore, that the spinal marrow and 
the spinal nerves, together with the medulla oblon- 
gata and the several pairs of nerves within the cran- 
ium, are all purely and exclusively the agents of ani- 
mal sensation, perception, and voluntary motion; 
and that the brain itself, instead of being a galvanic 
apparatus employed in generating the nervous power 
or vital stimulus of the whole system, is appropriated 
entirely to the intellectual and moral powers and 
manifestations, and has little more to do with the 
rest of the body than to depend on its general organic 
economy for its own sustenance, and to constitute the 
special organism through which the mind is acted on 
by the body, and in turn acts on the body — directly 
in the exercises pf the will, and indirectly in all 
mental excitements and emotions. 


The brain— the order of its development and the relations of its 
parts— Gall's views— Spunheim's views — Tiedemann's views — 
Number of cerebral organs described by Gall—Number added 
by Spursheim — Common centre of the cerebro-spinal system— 
Duplicate and symmetrical form of the system— Not so in the 
nerves of organic life— Connexion between the nerves of organic 
life and the cerebro-spinal system — Skin and mucous membrane, 
their structure and general functions as media of nervous con- 
nexion and sympathy — Organic and animal sensibility describ- 
ed — Centre of animal life no perception of, nor control over, tiie 
fiinctions of organic life — Nerves of organic life no animal sen- 
sibility—External senses and their relations-Touch, taste, smell, 
hearing, sight— Special senses of organic life— Sympathetic re- 
lations between the different parts in organic and animal life — 
The powerful sympathetic relations between the stomach, brain, 
and all othei parts— Sympathies, sources of happiness and of 
misery— Organic sympathies excited by poison— Morbid sensi- 
bility in nerves of erganc life— Sympathetic relations between 
tne nerves of organic life and the mind — Influence of the mind 
on the body — Of the body on the mind— Hereditwy predisposi- 
tion. «»tc. — Nerves larger and more pulpy in early life — smaller 
and rlrier in old age. 

261. The parts within the cranium remaining to 
be described, are the cerebrum or brain, and the 
cerebellum or little brain. The latter occupies the 
lower portion of the back part of the skull, and the 
former occupies the whole of the upper and front 
portion. In common lang^uage, however, all the parts 
within the cranium are collectively called the brain, 
and in the technical language of anatomy and physi- 
o^ogy, the encephalon, from two Greek words mean- 
ing ' in the head.* 

262. At first, the contents of the cranium and spi- 
nal canal are, as I have said (214), exceedingly soft, 
somewhat like the white of an egg. They gradually 
become more and more consistent, and assume the 
form of determinate structure and arrangement. It 
is not, however, until about the seventh year of life 
that the brain is supposed to have attained to that 
completeness of development and degree of consist- 
ency which fit it for vigorous functional exercise; 
and even at this age, the employment of it in severe 
and continued mental operations is neither safe nor 

263. I have already so fully described the natural 
order of the original development of the cerebro-spi- 
nal system (250), that I trust I shall not be misun- 



derstood if I now proceed to d^crihe the brain as it 
presenu itself to the eye of tlie anatomist, in tlie dis- 
leetion of the completely developed body, and apeak 
of parts as rising from others, which probably origi- 
nated separately, and in the progress of development 
became united. 

264. The medulla oblongata, or that portion of the 
spinal mnrrow which is within the nkutf, 1 have said 
{244 )j conalsu of three pairs of bodies nnited in a 
single bulb (ig, 15, m)—vi'R., the two pyramidal 
bodiea (A) which are continuations up of the two 
front portions of the spinal marrow (238), tho two 
restiform bodies which are continuations up of the 
two back portions of the spinal marrow, and the two 
olivary bodies (fig. 15^ i) lying between the other 
two pairSj and piirtly at the HideSi which are com- 
posed of gray matter thinly surrounded by white 
fibres J and by some anatomists are considered enfore- 
ing ganglion! . The bulb thus composed leans for- 
ward in the cranium j and rests in anterior surface in 
a fossa or groove formed for It in the basilar bone^ 
This brings the front portion ^ or the two pyramidal 
bodies^ partially under the others, so that the resti- 
form bodies, or the continuationa of the back portions 
of the spinal marrow, are placed somewhat above. 
Medullary fibres (250), continuing from these !ast 
named bodies, pass throtigh masses of the gray sub- 
stance, by which they are greatly augmented in num- 
ber, and are reflected backwards in nearly a borizon- 
ul line, and expanded into something like a fibrous 
membrane which by its peculiar foldjngs forms the 
little brain. The diverging fibres from each resti- 
forni body form a distinct IooBj so that the little brain 
consists of two lobes, the one on the right and the 
other on the left of the middle line* Some of the 
fibres of each of these lobes proceed forwards, andj 
taking a transverse direction, meet and unite on the 
middle Une at the top of the tneduHa oblongata^ form* 

Fig. 15. 

The bue of the hmin, exhibiting— a, the unterlor lobes ; It, th« 
middle lobee ; k. the poiCerJor lobefr prDJBctinf; o?^/, the littlB 
brfim; m, the it5C(Ju1U obWnguLa ; A, the pyramidal bodiet: i, 
tbe oliTiuy bQd.t«» ; d, the poam vaxDliJ; and 1, 2, J^, i, £, 6, 7, 
St S, lU, llr Ih th« dUfereat cn«b»l nena desesrlbed Id ths 

ing the principal ^mmissure or uniting portion of the 
little brain. This portion is sometimes called the 
pons or bridge, going from one lobe to the other ^ 
Hometimes it is called the annular protuberance ; and 
sometimes the transverse fibres (Fig. 15, d). Seve- 
ral pairs oi nerves within the cranium which I have 
described, have the superficial appearance of origi- 
nating in this body. Besides the transverse fibres, 
there are also others which connect each lobe with 
the quadrtgeminal bodies and the brain proper. It 
is eitremel^ difficult to describe the parts of which 
I am speakings in such a manner as to pr^ent a cor* 
rect image clearly and distinctly to the mind of those 
who have never seen a naked brain. Fig. 16, /, how- 
ever, is a very good illustration of the general exter- 
nal appearance of the little brain in its connexion 
with the cerebrum or brain proper. Yet to obtain a 
clear and accurate idea of it, the brain iuelf must he 
seen and ejcamined. 

265. The medullary fibres continuing from the 
pyramidal bodies of the medtiUa oblongata (fig. 15, 
A), together with tho^e from the olivary (i), and per- 
haps a few from the res ti form bodies, proceed forwards 
and upward^,, passing through masses of the gray sub- 
stance, which a.fe covered by the transverse fibres (rf) 
of the little brain ; the olivary fasciculi either tra- 
versing or becoming closely connected with the quad- 
Hgeminal bodies. Having arrived at the anterior 
edge of the annular protuberance (rf), considerably 
incJ'eased in number, they form what are caDed the 
crura cerebri, or legs of the brain. They uow plunge 
into the great ganglions of the brain, caUed by the 
old anatomists the optic thalatni (250), where they 
are again very greatly increased in number. Accord- 
ing to Spurzhemi, the fibres or fasctcuii, from the 
olivary and restiform bodies, traverse the posterior 
and middle portions of the great ganglions, from 
which they diverge and form the convolutions of the 
upper and posterior parts of the hemispheres j and 
the fasciculi from the pyramidal bodies tra- 
verse the anterior portion of the great gang- 
lions, from which they pass into the smaller 
ganglions, called the striated bodies (250), 
where, again, they are exceedingly augmented 
in number, and from which they diverge and 
form the inferior, anterior, and external convo- 
lutions of die front and middle lobes of the 
brain (Fig. 15, a^ A). The pyramidal bodies 
{k) of the medullary oblon^ts he considers 
the rudiments of such parts of the brain as be- 
long to the intellectual operations, and, in man^ 
the olivary {i) and part of the restiform bodies, 
as the roots of those parts that pertain to the 
affective manifestations. And in accordance 
with this view, he says that in the animals 
below man, that portion of the legs of the brain 
which is formed by the olivary fasciculi, is much 
more voluminous than that portion whieh is 
formed b^ the pyramidal fasaculi ; and as we 
desceod in the scale of being, its relative pro. 
portion increases continually j while in man, 
that portion which is formed by the pyramidal 
fasciculi constitute two^thirds of each cerebral 

266, In regard to the arrangement of the me- 
dullary fibres In the formation of the convoln* 
tioni and commiasures of the brain, there is a 
wide difference of opinion between the most 
eminent anatomists. ' The convolutions inter- 
naUy consist,* says Spur^heim, *of white fibres, 
which are covered on their extremities with 
cineritious substance. These fibres, which ter* 
minate the nervous bundles of the cerebral 
crura, are not all of the same length. Many, 
especiaJly of those which are situated on the 
outer sides of the convolutions, terminate im- 
mediately beyond the exterior walls of the 



cavities ; the others extend to distances progres- 
sively greater as they run more centrvdly; those 
of the interior extending the farthest of all. It 
is in consequence of this peculiar structure that pro- 
longations and depressions are formed on the surface 
of the hemispheres. The cineritious or gray sub- 
stance foUows all the forms composed by the white 
fibres, and covers every elevation and depression with 
a layer. 

267* Concerning the commissures of the brain, or 
those parts which unite the two hemispheres, he says 
— * They are formed by the converging ^e». Nothing,* 
he continues, < can be easier than by dissection to 
prove the two orders of cerebral fibres the diverging 
and converging, and to show that the mass or bundle 
called the corpus callosum belongs to the converging 
order.' Yet Tiedemann, whose authority on this 
subject is perhaps equal, if not superior, to that of 
any other man, declares that these converging fibres 
have only an imaginary existence, that they are not 
to be found in the brain, and that the corpus callosum 
is formed before the convolutions (which according to 
Spurzheim give rise to converging fibres) begin to ap- 

268. I confess that my own inquiries and investiga- 
tions, which have been somewhat diligent and pro- 
tracted, have resulted in impressions much more in 
accordance with the views of Tiedemann than with 
those of Gall and Spurzheim, in regard to the con- 
verging fibres, and the formation of the commissures 
and convolutions of the brain. If nothing can be 
easier than by dissection to prove the two orders of 
cerebral fibres, it is very remarkable that so few have 
ever succeeded in satisfying themselves by actual dis- 
section, of the existence of the converging fibres. I 
have conversed with many able anatomists who had 
dissected many brains, and who believed and taught 
the doctrine of Gall and Spurzheim concerning these 
fibres ; but I never yet saw the man who by actual 
dissection had demonstrated their existence. 

269. According to Tiedemann, the medullary fibres 
that issue from the cerebral ganglions which I have 
already described (265), at first form a thin fibrous 
membrane on each side of the head. These mem- 
braneSj in the progress of development, curve their 
superior edges in towards the middle line, and these 
edges gradually meet and unite, and thus form the 
corpus callosum, or great cerebral commissure ; and 
by so doing, at the same time, form the two hemis- 
pheres of tne brain ; which as yet are in a membra- 
nous state, like two bladders, without any appear. 
ance of convolutions : but the membrane is consider- 
ably thickened by the additions of new medullary 
matter on the exterior surface. In this state of the 
brain the fibres are to be traced from the medulla 
oblon^ta to the corpus callosum, and it is evident 
that the fibres which terminate in and form this com- 
missure, are the same that come from the legs of the 
brain ; and were the skull sufficiently capacious for 
an entire development of the cerebral nemisphere in 
this form, the human brain might come to fuU matu- 
rity of organization and of functional power without 
a single convolution. In cases of hydrocephalus, 
where the hemispheres are completely expanded, they 
are merelv brought back into that membranous 
state in which they were at first. And this, we 
know, takes place without any perceptible disturbance 
of the cerebral function. 

270. * Were the diverging fibres of the great cerebral 
ganglions prolonged directly into the corpus callosum,' 
says Spurzheim, ' it would be extremdy difficult to 
understand how they could be elongated to the degree 
occasionally observed in hydrocephalus. But the 
difficulty here contemplated is purely imaginary. It 
is not claimed that in the normal state of a fully devel- 
oped brain the fibres proceed directly from the gang- 
lions to the commissure, but ^at the membrane 

formed by these fibres is so folded in and out upon 
itself, as to form what are called the convolutions of 
the brain, and so as to bring the greatest extent of 
surface within the capacity of the skulL It is there- 
fore very easy to understand how water, slowly accu- 
mulating in the cavities of the brain, gradually raises 
up the corpus callosimi, and enlarges the capacity of 
the skull, and unfolds the hemispheres into tneir 
expanded membranous form without lacerating any 
of the cerebral texture, or disturbing any cerebral 
function. It is before the convolutions are formed, 
and those cases of hydrocephalus in which all the 
convolutions are unfolded, and the hemispheres com- 
pletely expanded into their original membranous state, 
that the fibres proceed directly, or rather in a curved 
line, from the ganglions to uie corpus callosum. I 
have not found it very difficult to unfold the hemis- 
pheres of a recent brain in this manner, and spread 
it out into an extended membrane with no other la- 
ceration of the parts than was necessary at the edges, 
in order to bring a natural hemisphere into a plane ; 
and when thus unfolded, it is very easy to see the 
blood-vessels ramifying over the whole internal sur- 
face, and to perceive the medullary fibres radiating 
like the sticks of an open fan, from the medulla ob- 
longata to the ^nglions, and from the ganglions to 
the great commissure. 

271. According to Tiedemann and to my own con- 
victions, then, when the cerebral hemispheres are as 
fiilly developed in the extended membranous, or blad- 
der-like form, as the normal capacity of die skull 
will allow, the membrane, now consisting of the fibrous 
arrangements of the white substance, with a thin 
covering of gray substance on the external surfieice, 
begins to gather into folds, so as to continue the en- 
largement of its surface, and still accommodate itself 
to the capacity of the skull. In this manner the de- 
velopment of the hemispheres proceeds, till a nervous 
membrane is folded up in the cranial cavity, the area 
of whose surface is several times greater than that of 
the inner surface of the skull ; and until that thin 
membranous arrangement, which at first was ex- 
panded and smooth, is so closely folded upon itseUT, 
and by the general curving of the mass to adapt itself 
to the capacity and shape of the skull, the internal 
parts are so closely pressed together and compacted as 
to give to the external surface of the hemispheres 
those elevations and depressions which are called the 
convolutions, and to the medullary matter the appear- 
ance of a thick solid wall or mass. By the general 
curving of this wall, also, in order to come into the 
spherical shape of the skull, the corpus callosum or 
great commissure is brought down on the middle line 
near to the base of the brain, and thus are formed, 
by the same disposition of parts, the great external 
fissure extending from the forehead to the occiput, 
between the two halves of the brain (fig. 16), and 
the great intern^ ventricles or cavities of the hemis- 
pheres. Other smaller cavities are likewise formed 
at and near the centre and base of the brain, by the 
relative position of different parts. But as the mmute 
description of them would serve in no degree to illus- ' 
trate any known physiological principles, I shall say 
nothing more concerning them. 

272. Each hemisphere of the brain thus developed 
is subdivided, in we descriptions of anatomy, into 
three lobes : an anterior lobe lying in the forehead 
(fig. 15, a), a posterior lobe lying in the back part of 
the head and over the little brain (Ar), and a middle 
lobe lying in the region of the ear (6). Each of these 
lobes, again, is composed superficially of a number of 
apparent convolutions of the cerebral substance, so 
that the whole external surface of the brain is a suc- 
cession of irregular elevations and depressions ; and 
this irregular or uneven surface, it will be remem- 
bered, is everywhere covered by a thin layer of the 
gray substance (fig. 16). The vascular membrane 



c^ed th& pi<t mater f which Burrounda the ipmal niar> 
row (2119), corner up and expand! b over the little brain 
and brain proper, adhering in all pariit cloiftely to the 
■utf&ce, and dipping into every depressions fissure, 
and cavity. Over this ia iipread the anicihtioid or spi- 
de?**s-web membronej which also continues up from 
the spinal marrow, and is everywhere constantly 
moistened with a serous 6uid ; and which, beside 
covering the cerebrum and cerebeHum, fortns a sheath 
or envelope for all the nerves und all the vessel* which 
enter or issue from the skull ; and finally^ envelopiii(^ 
the whole, the strong tibrous membrane called the 
dwra^mat&Ty continues up from the spinal canal^ and 
expands and linet tlie inner surface of the akuJJ 
throughout, dips down, by what is called the falci- 
form procesa, between the hemispheres of the brain 
to the corpus callosmn, forms a partition between the 
posterior lobes of the brain and the little brain called 
the ten tori litn^ and also separates the two lobea of the 
little brain* 

Fig. la* 

Top or tlie braJB, shQwing the eoiif Dlutiont* and theflmm 
beiweeQ t&u twa hemisphuref ,. 

^3. The two hemisphere of the brain are united, 
AA 1 have aaidj on the middle line by the great cotn- 
misBure or corpus callosnm whit'h lies near the ba^e. 
There are aLw smaller coniniissurea in the anterior 
and posterior parts* But the principal bond of unicm, 
&nd that on which the unity of the brain and of Its 
functionA, as a single organ, or as a single sy intern of 
organs, mainly depends. Is established at the focal 
point, at Of near the top of the medulla oblongata, 
from which the fibres composing the legs of the brain 
rise and diverge. * The corpus calloaum,' nays Dr, 
Spuraheim, * may be split through its entire length j 
without destroying the unity of function of the two 

274* The fibrous arrangement of the medullary 
substance of the brain (lii2)j and the disposition of 
the fibre* in the texture and general conformation of 
the cerebral hemisphereSj have, of late years, been 
rendered matters of very considerable interest by the 
Tiews, originally advanced by Dr, Gall, and since 
advocated by Spurzheim and otber«, concemlng the 

relation existing^ between paitictilar parti of the brain 
and particular intellectual and moral powers and 

275. According to these views as first advanced by 
Gall, a certain number of medullary fibres radiating 
from the cerebral ganglions in each hemisphere, form 
a fasciculus or bundle, which proceeds to the surface 
of the brain, and constitutes a special organ, the sin^ 
gle and exclusive function of which is the manifesta- 
tion of a speciiic propenstity, sentiment^ or intellectual 
power. Of these special organs, fiall described and 
located twenty-seven pairs, including the two lobes 
of the cerebellum as a single pair ; the organs of one 
hemisphere corresponding precisely with those of the 
other, as one eye or ear does with the other. 

276. Spurzheim, who was a pupil of Gall^s, em* 
braced the views of hid master with jEp-eat confidence 
and zeal, and from that hour devoted his whole life 
with untiring industry to those researches and inves. 
ligations by whicii he hoped to erect the theory into 

a complete and well-established science; and 
if he did not live to accomplish all that he 
desired, he certainly succeeded in producing 
a powerful impression on the mteUectual 
world, and in convincing though nds of the 
correctness of his doctrines. He was pro- 
bably more successful in unhiding the brain, 
and did more to introduce a correct mode of 
dissecting and studyingthat importstut organ, 
than any other man. But such is the soft- 
ness of the cerebral substance, and llie deli- 
cacy of its tissue, that it is impossible, by 
any artificial meanSj to push our enquiries 
very minutely into the details of its intimate 
itructure anJ arrangement, with an entire 
certainty of ascertaining the truth on every 
point. Hence, notwithstanding the con- 
fidence with which Spurzheim insisted on 
the existence of an order of converging fibres 
which originate in the cerebral convolutions 
and terminate mainly in the corpus callosum, 
and declared that * nothing is more eaa^ 
than to prove this by dissection,' yet all bis 
followers have been obliged to receive this 
purely as a matter of faith, for no one, I 
believe^ has been able to demonstrate the 
truth of the statement. The course pur- 
sued by Tiedemann is, therefore, a far more 
correct and sure way of coming at the truth, 
in regard to the intimate texture of the 
brain. He carefully watched the cerebral 
development in all its stages, from the first 
appearftnce of any of its parts to its fuU 
maiunCy. He saw the several parts in their 
rudiments, saw them in their more advanced 
state, saw the thin membranes of the hem- 
ispheres before they were united to the cor- 
pus caUosum, saw them when partially and when 
G^mpleteliy united, saw the two hemispheres when 
thus united, expanded and smooth like two distended 
bladders lying side by side, saw them when they first 
began to gather into folds, and saw them when closely 
folded in the full-formed braia. Yet even in this 
mode of investigation it was possible for him to be 
deceived in regard to the origin and disposition of 
some of the parts ; but the probability of error in 
this mode is incomparably less than in that pursued 
by Spurzheim. 

277. I have already presented Spurzheim's deacrip- 
tion of the cerebral convolut'oni, and of the manner 
in which they are formed (266), But if Tiedemann is 
correct in regard to the membranous arrangement of 
the medullary fibres, and of the folding of that mem. 
hrane so as to form what are called the convolutions 
of the hemispheres in the manner I have described, 

(271), and that he is correct, I must still insiat, is fully 

proved by the complete unfolding of the brain into its 



membranous form, in some cases of hydrocephalus, — 
then Spurzheim was in error, not only in regard to 
the existence of an order of converging fibres, but 
also in regard to that arrangement of the diverging 
fibres which he describes in speaking of the forma- 
tion of the convolutions. 

27& But if it were fully demonstrated that Spurz- 
heim was in error on both these points, it would not 
necessarily foUow that his theory concerning the re- 
lation between certain parts of the brain and certain 
powers of the mind is incorrect. The truth of this 
theory is not to be demonstrated by cerebral anatomy, 
but by cerebral physiology ; and it is equally possible 
for such physiological powers to be possessed by the 
brain, whetner its organization is according to the 
descriptions of Spurzheim or those of Tiedemann. 

279. I have said that Gall described and located 
twenty-seven pairs of cerebral organs. To these 
Spurzneim added eight pairs, which he described and 
located ; and conjectured two pairs more, the location 
of whidi he only suggested. So that, according to 
Spurzheim, we have thirty-five, and perhaps thirty- 
seven, or more pairs of cerebral organs appropriated 
to the propensities, sentiments, and intellect. The 
two pairs conjectured by Spurzheim have with more 
confidence been described and located by some of his 
followers ; and, indeed, some of the more bold and 
zealous phrenologists multiply and locate organs ad 
tibUumy to suit their convenience, to meet their exi- 
gencies, or according to their convictions from obser- 
vation. The character and location of these organs 
I shaU describe according to the views of Gall and 
Spurzheim, when I come to treat of the physiology of 
the brain (534). It may be well, however, in this 
place, to say that phrenologists, so far as I am in- 
formed, are not decided in opinion whether the think- 
ing power of the brain belongs more especially and 
intimately to the gray substance of the surface, or to 
the white medullary fibres which form the convolu- 
tions (161, 162). 

280. From the view which I have presented of the 
cerebro-spinal system, it will be perceived that all the 
nerves of the trunk and extremities appear to con- 
verge, as it were, toward the head of the medulla ob- 
longata (251), and all the nerves and medullary fibres 
within tne cranium converge towards the same point. 
All the parts above this point may be destroyed 
by slow disease, without destroying the power of 
animal sensation and of voluntary motion ; and all 
the parts below the medulla oblongata ma^ be para- 
lyzed by disease, without immediately abohshing the 
intelleetual powers. It may, therefore, be asserted 
with great confidence, that the grand centre of ani- 
mal li^ is at or near the top of the medulla oblongata. 
I do not, however, intend to imply that vitality pecu- 
liarly resides at this point, but that here seems to be 
such a focal point of the whole nervous machinery of 
the cerebro-spinal system, that we can at this place 
put our finger on the whole at once, and instantane- 
ously arrest all the functions of this system of nerves. 
It is therefore the centre of animal perception and of 
voluntary action ; the point to which all animal sen- 
sations are directly conveyed, or by which they are 
perceived, and from which all the mandates of voli- 
tion are transmitted directly to the muscles of volun- 
tary motion. 

281. I have already more than once alluded to the 
duplicate form of all those parts in the human body 
which belong to animal life (238). If the body be 
divided on the middle line, it will be found to consist 
of two precisely corresponding halves : the bones, the 
muscles, and the nerves of one side, correspond almost 
exactly with those of the other. The parts uniting 
on the middle line are composed of two corresponding 
halves, as the tong^ue, the nose, the mouth, etc. ; 
while those removed from the middle line are in cor- 
responding pairs, as the eyes, the ears, the upper and 

lower extremities, etc. The nerves of the two halves 
of the cerebro-spinal system are very exact and sym- 
metrical in their resemblance to each other. The 
right and left half of the brain and spinal marrow, 
and all the nerves connected with them, are almost 
precisely alike. Yet it is an interesting fact that 
this symmetry is less perfect in man than in the ani- 
mals below him. ^ Considered either in regard to 
symmetry or structure,' says Meckel, ' the nervous 
system of man is less regular than that of other ani- 
mals, even those which are nearest to him. In fact, 
the halves of the nervous system correspond more per- 
fectly in the mammalia, and the deviations from the 
normal state in those animals are rarer than in man.' 
This difference is very certainly not an aboriginal one, 
but is most unquestionably a degeneracy in the human 
species, and without doubt has resulted from the volun- 
tary habits of man. 

282. In the domain of organic life, though there is 
some approach to the duplicate form, yet there is no 
regularity or symmetric correspondence. The two 
lun^s do not exactly correspond, nor do the two halves 
of the heart. Indeed there is an evident oneness of 
system and economy in the domain of organic life. 

283. We have seen that this system of nerves pre- 
sides over all the vital functions by which the body is 
formed and sustained (218 — ^231), and that the nerves 
of animal life, with their muscles, bones, etc., are 
purely organs of external relation, whose office it is 
to perceive those external wants, the supply of which 
requires their exercise, and to perceive and procure 
those external materials by which the internal wants 
are supplied (233). These important functional rela- 
tions make it necessary for the two systems of nerves 
to be so connected that the requisite media of commu- 
nication shall be established between them ; and the 
mutual dependencies of the two systems also require 
them to be intimately reciprocal in sympathy. I shall 
therefore now proceed to speak of these coknexiohs 


284. It will be recollected that, when treating of the 
nerves of organic life, I spoke of a range of ganglions 
lying on each side of the back-bone (220), connected 
by intermediate cords, and extending from the base of 
the skull to the lower extremity of the spinal column ; 
and that these ranges are connected with the great 
centre of organic life, by numerous cords radiating 
from that centre and terminating in many of these 
peripheral or limiting ganglions. Of these ganglions 
there are usually on each side three in the neck, twelve 
in the region of the back, five in the region of the 
loins, and three or four in the sacral regions. These 
ganglions lie near where the spinal nerves of animal 
life are connected with the spinal marrow ; and us the 
spinal nerves pass by the ganglions, each ganglion 
gives off two branches, which proceed outward a short 
distance, and join the corresponding spinal nerve. 
One of these branches is usually larger and more pulpy 
than the other, and sends some twigs to the muscles 
between the ribs. This is supposed to be more espe- 
cially the medium of communication from the ganglion 
to the spinal nerve : and the other, which is smaller, 
whiter, and gives off no twigs, is supposed to be the 
medium of communication from the spinal nerrj to 
the ganglion. AU the ganglions in the two ranges 
also give off filaments which go with the nerves of 
animal life to the muscles of voluntary motion ; and 
more especially to those voluntary muscles which are 
concerned in the function of respiration. The highest 
ganglion of the range on each side, lies at the base of 
the skull, and sends a branch upwards, which, divid- 
ing into twigs, forms a kind of plexus around the main 
artery of the brain, and passing with it into the cra- 
nium, unites with two or three cerebral nerves, and 
particularly the trifacial, which is so important a nerve 
of the head. This last nerve also, it will be remem- 
bered, after passing out of the cranium, unites in itt 



▼mrious ramifications extensively with the nerves of 
organic life (254). Such are the connexions between 
the limiting ganglions of organic life and the nerves 
of animal life. 

285. The upper central connexions are mainly es. 
tablished by the pneumogastric. This nerve, it will 
be remembered, issues from or near the grand centre 
of perception and action of the nerves of animal life 
(245), and by its branches forms connexions with 
almost every nerve, both animal and organic, in the 
region of the throat and neck, and also forms exten- 
sive connexions with the nerves of organic life in the 
thoracic cavity, and unites freely in the stomach with 
the nerves coming directly from the great centre of 
organic life, and finally sends some twigs directly to 
that centre itself (247). 

286. Another and more extensive and general con- 
nexion is formed between the two systems of nerves, 
by that arrangement on which the body in all its parts 
and tissues depends for sustenance. The nerves of 
organic life appropriated to the vascular system, and 
which preside over all its varied functions, penetrate 
with the vessels to which they belong, into every struc- 
ture of the body. Even the brain and spinal marrow, 
and all the nerves of the body, are nourished by blood- 
vessels over whose functions the nerves of organic life 

E reside. By this universal presence and functional re- 
ition, the nerves of organic life are brought into im- 
portant connexions with those of the cerebro-spinal 
system. This species of connexion is largely formed 
in the extended membrane which constitutes the 
covering of the body ; and, therefore, for the sake of 
showing still farther the anatomical connexions and 
functional and sympathetic relations between the do- 
mains of organic and animal life, I shall introduce 
in this place a general description of the skin, re- 
serving the more minute details till I come to speak 
of its particular functions. 

287. In the vegetable kingdom there are some spe- 
cies which may be torn up by the roots and inverted, 
placing their tops downwards in the earth, and their 
roots in the place of their boughs, and the order of 
their vegetation will change, and their tops will become 
roots and their roots boughs with their twigs, leaves, 
etc. So in the animal kingdom there are some spe- 
cies which may be turned inside out, and they will 
live on, apparently as well as before ; the membrane 
which was internal performing all the necessary func- 
tions of the external, and that which was external per. 
forming all the n?c3ssary functions of the internal skin. 
This correspondence of anatomical structure and func- 
tional capability between the inner and outer skin, is 
continued to a considerable extent through the whole 
animal kingdom, up to the human species. In man, 
a peculiar membranous texture of cellular tissue covers 
the whole external surface of the body like a sack ; 
continuing over the lips and up the nostrils, the same 
membrane lines the cavities of the month and nose, 
covering the tongue, etc., and still continuing back- 
ward and downward, it covers and lines all the parts 
of the throat, — lines the windpipe, and extends thro* 
all its innumerable branches in the lungs, lining 
all the air-passages and cells, and presenting to the 
air in the lungs an extent of surface equal to the whole 
external skin of the body ; and some think, much 
greater. The same membrane also continues down 
the meatpipe, lining it and the stomach and the whole 
intestinal canal and the ducts which open into it. 
This membrane, throughout its whole extent, is a 
delicate net-work, with an almost infinite number of 
extremely small meshes. Through these meshes pene- 
trate in countless numbers the almost inconceivably 
minute terminations of capillary vessels of the san- 
g^iiferous and lymphatic systems, with their accom- 
panying and presiding nerves. Besides these, innu- 
merable filamentary extremities of the nerves of sen- 
sation pass througn the meshes of the membrane in 

the same manner. These vessels and nerves are so 
minute, so numerous, and so intimately associated, 
that it is not possible to puncture the skin in any 
place, with the point of the finest needle, without 
wounding both a nerve and a blood-vessel. According 
to some anatomists, this vasculo-nervous web is so 
constructed as to form a kind of nap on the exterior 
face of the membrane, somewhat like the pile upon 
velvet. This nap, however, and particularly that 
portion of it which consists of the nerves of sensation, 
is longer and thicker in some parts than in others 
(242) ; as on the ends of the fingers, etc., externally, 
and in the stomach and small intestines internally. 
To lubricate these exquisitely delicate little organs, 
and preserve them in a condition proper for the per- 
formance of their functions, they are everywhere sur- 
rounded by or imbedded in a thin body of mucus. 
This, on the external surface, is called the rete muco- 
sum, and contains the substance which gives the color 
to the skin ; being black in the negro, copper-colored 
in the Indian, white in white people, etc. Still far- 
ther to protect these delicate little organs from the 
rude and improper contact and influence of external 
things, the whole external surface is covered with a 
thin transparent horny substance called the epidermis 
or cuticle. This, however, becomes very thick and 
hard on parts subjected to much friction, as the bot- 
toms of the feet, the palms of the hands and insides 
of the fingers of laboring men, etc. On the lips, nos- 
trils, etc., where the external skin fades into the in- 
ternal, the cuticle is extremely thin. In some ani- 
mals a very delicate epidermis or cuticle continues 
inward, lining the mouth, meatpipe, and stomach; 
and some anatomists have supposed this to be the case 
in man.* 

288. We see, then, that the external surface of the 
body, and the cavities of the mouth, nostrils, wind- 
pipe, air-passages, and cells of the lungs, meatpipe, 
stomach, intestinal tube, etc., constitute the confines 
of the incorporated living system, through which it 
communicates with the external world; and all these 
surfaces are covered by the same continuous, delicate, 
net-like membrane, through which must pass every 
thing that enters into or issues from the living system. 
And for the purpose of introducing into the system 
all materials necessary to sustain the vital economy, 
and of conducting from it all that the vital economy 
has no further use for, or that would clog or oppress 
or disturb or destroy the operations of the economy, 
the innumerable vessels which I have just named 
pass through the meshes of the membrane, and form 
a vascular web upon its exterior face ; and with these, 
also, the myriads of most exquisitely delicate feelers, 
whose office is with strictest integrity to give their 
respective centres of perception and action all neces- 
sary information concerning the presence and qualities 
of external things, with reference to the interests of 
the vital economy. 

^ 289. In regard to the substances conveyed into the 
living system, the little vessels differ in function in 
the different parts of the internal and external sur- 
face, as we shall see hereafter ; and this is also true 
concerning the substances conveyed out of the system. 
Still, however, there is, to some extent, a general oor- 
respondence of function throughout the whole confines 
of the living system ; and especially the eliminating 
functions, or those which convey substances from the 
body. The external skin, and that of the lungs and 
alimentary canal, in many respects very nearly re- 
semble each other, in regard to the substances which 
they throw off from the system ; and they are, to a 
considerable extent, reciprocal or vicarious in their 
offices, the excess of one corresponding with the sup- 

* Doctor Homer, of Philadelphia, has recently demonitrsted 
the existence of an epidermis throughout the whole length of the 
alimentary canal, of which I shall speak more particularly when 
I come to describe the particular anatomy of the paitt. 



pre««ian of another^ The interna] ikin^ which lines 
the mouthy nofitrilaH» windpipe} meatpipe, Atom&ch, tn- 
teatinal tube, etc, is, in the description a of anatomy 
and ph jAioIogy, called the mucous membrane, 

2.90. The myriads of little feelers or fiJamentary 
extremities of the nerres of sensation in the external 
akin, are nervea of animal life, and are connected with 
the back portion of the spiaaZ marrow (242), and 
through it with the top of the medulla oblongata and 
brain. Tho»e of the internal skin or mncoua mem- 
brane, are nerves of organic life (230)^ and are con^ 
nected with their special centres of perception and 
action, and through them with the grand centre of 
organic life (226). The nerves of animal sensibility 
also ex^tend to all portions of the mucous membrane 
which line or cover parts subject to the control of the 
i¥ir L, or which perform voluntary functions, as the 
mouth, throat, etc. 

291. Thus we »ee that the skin ^ as a whole, conMi- 
tutes a vetry extensive medium of connexion and fune^ 
tbnal relation between the nerves of organic and those 
of animal life ; and the sympathetic relations and re- 
ciprocities are equally direct and powerful. The mu- 
cous membrane of the alimentary canal and liinga 
sympathizes directly and powerfully jn all the irrita- 
tions and affections of the external skin ; and the 
whole extBrnal skin, in turn, sympathizes in all the 
irritation a and affections of the muc^>uB membrane : 
this h parti cu la rlv the ca^e in all morbid affections of 
the external and internal skin^ 


292. I have often spoken of organic and animal 
sensibility. It i» very important thst the meaning 
of these terms should be fully understood. Strictly 
ipaking, there are several species of sensibility in 
tKe human body. That vital property of the muscles 
which renders ihem 8 usceptihle of the action of their 
appropriate and other stimuli, may be considered a 
species of organic aenalbilityj hut it'is generally called 
irritability; and the term sensibility is only ap- 
plied to the nerves. To make this deeply interesting 
subject as plain as possible, it is necessary tbat I 
should reeBpitnlate for a moment. I have said that 
the large nervous mass lying back of the pit of the 
stomach is the great, primary, and com m on centre of 
organic life, and that the numerous smaller masses, 
or subordinate brains, are the special centres of par^ 
ticular organs or apparatuses of organs ; and that the 
top of the bead of the spinal marrow is the centre of 
the nerves of animal life, or the centre of the nerves 
of external relation, 

^ 293. Now let us understand the extent of the func- 
tional powers of these several centres. 

In the first place, the special centres of organic life 
(219) preside over the functions of their particular 
organs ; and so far as each particular function is iso- 
lated from the functions of other organs^ the centre 
which presides over it is an independent and sove- 
reign centre of perception and action ; but so far as 
it la immediately associated with the function or func- 
tions of other organs^ the presiding centre is con fed e- 
rated with other special centres ; and so far as each 
function is related to the great common centre as a 
constituent part of the cotnmou whole of organic life, 
each special centre is subordinate to the great com- 
mon centre ; and so far as the common whole of 
organic life requires the exercise of the organs of ex^ 
ternai relation, it is in a manner subordinate to the 
centre of animal life. The functional powers of tbia 
last centrei, then, are, first, the perception of the 
wants of the internal system as a whole, such as the 
want of air, food, drink^ etc. ; second, the perception 
of the external materials and means bv which the 
internal wants can be satisfied | and thir^, the exer* 
tlon of tbat infiuence by which the voluntary muscles 
are contracted, and the motions are performed, neces- 
iarf £ia aupplylng the internal wants. 

294. W& see then, that when there is a general 

state of health throughout the body, and all things 
in the vitiil domain are as they should be, and every 
function properly performed, the special centres only 
have perception of what is taking place in their owu 
appropriate spheres, while the great common centre 
has perception of the general condition of each par- 
ticular organ, and presides in a general manner over 
the whole domain of organic life. The centre of ani- 
mal life, therefore, has no perception of, nor control 
over, the particular functions of organic life. It only 
has cognizance of those general wants of the internal 
system which, though referred to particular organs, 
aVe still the common wants of the whole system. The 
functions of the stomach, intestinal canal, liver, pan- 
creas, and all the other organs within the exclusive 
domain of organic life, are, in a state of perfect health 
and good order, no more perceived by the centre of 
animal life, than they would be if they belonged to 
another distinct individual animal (228), Hence we 
say that the nerves of organic life have no animal sen- 
sibility. They may in a state of health he touched, 
cut, or lacerated, and the animal will suffer no pain, 
because the centre of animal perception has no con- 
sciousness of the act. But the performance of the 
functions of external relation, over which the centre 
of animal life presides, requires that this centre should 
have an extensive perception of external things with 
all their qualities and conditiouji. The qualities of 
density or resistance, heat, cold, etc.. must be/?// by 
the animal. Hence a part of the nerves of animal 
life (242), are endowed with the vital power of con- 
veying to the centre of animal perception the impres- 
sions of touch, heJit, cold, etc. ; and as the things and 
qualities in relation to which this sense exists, may 
annoy and injure the body in every part, the sense is 
universal in the domain of animaJ life. The whole 
external skin is largely supplied with nerve^ which 
constitute it a general organ of touch.. The limits of 
the internal skin^ and the muscles or flesh generally, 
also receive a measured supply of these nerves. ThAt 
property or power of the nerves of animal life, then, 
which enables us to feel heat and cold^ and to know 
when any thing wounds or touches us, and to perceive 
the qualities of "hard, soft, rough, smooth, etc., is what 
is usually called common animal senslhility ; an,d the 
exercise of this power, or the pleasurable and painful 
feeling excited in these nerves by contactor otherwise, 
we call animal sensation. This, I have said (242), is 
the fundamental faculty of external relation, and in 
some degree is always present when animal life exists. 
It IS a specific power which gives iheceutre of animal 
life the perception of certain qualities of external 
things, and is as truly a special sense as any in the 
body (253). But there are other qualities of external 
things which exist in relation to organic life, that a^e 
not perceived by this sense or power. For the per- 
ception sjf these, therefore, the animal is endowed 
with other special senses or faculties of external rela- 
tion. The first of these, and that which comes near- 
est to the sense of touch, and Is perhaps most inti- 
mately associated in organization with it, is the sense 
of tasto (254), by which the animal perceives certain 
qualities of external things which relate to the ali- 
mentary wants of organic life, such as sweet, sour, 
bitter, etc The next, in the order of its functional 
character, is the sense of smell (253), by which the 
animal perceives certain other qualities of external 
things which relate to the respiratory and alimentary 
wants of organic life ; such as the various agreeable 
and disagreeable, salutary and baneful odors. The 
sense of hearing and the sense of sight are faculties 
established not only in relation to the wants of or- 
ganic iifej but to the general interests and welfare of 
the body as a whole ; and, in man, these two faculties 
are more extensively and ecninently the instruments 
of the soul, in the performance of its higher fnnctioni. 



295. Now let it be didtinctly remembered that each 
of these senses or faculties of external relation is a 
power by which the centre of animal life perceives 
certain qualities of external things ; and that the pe- 
culiar vital endowments of each organ of special sense 
precisely fit it for the perception of those particular 

Sualities, in relation to which it is established ; and 
berefore these faculties are never vicarious in their 
functions (253). The eye never hears, the ear never 
tees, etc. The eye is only fitted to appreciate the 
properties of light, the ear of sound, the nose of odors, 
the tongue of tdste, and the fingers and external skin 
universally the tangible properties. 

296. With these explanations of animal sensibility, 
or the powers of external perception, let us return to 
the domain of organic life ; and there, though we find 
no animal sensibility, yet we shall find the rudi mental 
prototypes of all the external senses, each organ pos- 
sessing an organic sensibility as exquisitely delicate 
as the special sensibility of the nose or ear or eye, and 
as perfectly fitted to perceive and appreciate the qua- 
lities of things in relation to which it was constituted 
by a wise and benevolent God, as either of those spe- 
cial organs. Organic sensibility, then, as a general 
property, is the po^ver of the appropriate nerves of 
organic life to receive and convey to their special or 
general centres, the impressions made upon them by 
the substances contained in the organs to which they 
are distributed ; but this sensibility has nice and im- 
portant shades of difference in the different organs, 
adapted to the constitutional purposes of each parti- 
cular organ. Thus, the organic sensibility of the 
stomach is adapted to the properties of the food de- 
signed for tr e nourishment of the body, and the or- 
ganic sensibility of the intestinal tube is adapted to 
the properties of the chyme, etc., that of the lacteals 
to the chyle, that of the arteries, etc., to the blood, 
that of the biliary vessels to the bile, etc. But this 
very adaptation of the nerves of organic sensibility to 
the properties of appropriate substances, unfits them 
for the presence of improper substances ; and, conse- 
quently, when such substances are introduced into 
the stomach and other organs, they are the causes of 
irritation, disorder, and disease ; and in a natural and 
healthy state, always in proportion as they are un- 
adapted to the peculiar sensibility of the organ, and 
unfitted for the supply of the vital wants, or are of a 
character unfriendly to the vital interests. 

297. In regard to the sympathetic relations of 
parts, there is a very considerable difference between 
the nerves of organic and the nerves of animal life. 
The organs of animal life, so far as their sympathetic 
connection depends on the cerebro-spinal nerves, are 
comparatively isolated. A hand or a foot, an ear or 
an eye, or even a lobe or hemisphere of the brain, 
may be diseased and destroyed, and the correspond- 
ing and other organs of animal life will suffer very 
little direct sympathy. But in the domain of organic 
life, all parts sympathize with each, and each with 
all. If the stomach, in a healthy state of itself and 
of the whole system, receives a portion of food which 
is perfectly adapted to its peculiar sensibility and to 
the real wants of the vital economy, it is healthfully 
excited, and its general condition is agreeable, and 
all the other organs sympathize directly in the gene- 
ral condition of the stomach, rejoicing with it, and 
performing their own functions with a livelier and 
more gladsome energy ; and, on the other hand, if, 
by the ingestion of an improper substance, or any 
other cause, the stomach is irritated or disturbed to 
an extent which affects its general condition, all the 
other organs sympathize in that condition, and their 
functions are commenyurately disturbed, being either 
accelerated or retarded in an unhealthy and injurious 

298. In the same manner, also, all the other organs 
sympathize with the intestinal eanal^ with the liver. 

kidneys, etc. But the degree of sympathetic influ- 
ence which each organ has on the others, is always 
proportionate to the functional importance of the or- 
gan in the system, and the nearness of its nervous re- 
lation to the great centre of organic life. Hence the 
stomach holds an immensely important station in the 
assemblage of vital organs. Supplied as it largely is 
with nerves directly from the great centre of organic 
life (231), and with the pneumogastric, from the cen- 
tre of animal life (245, 285), and associated by plexu- 
ses with all the surrounding organs, it sympathizes 
more directly and powerfully with every other inter- 
nal organ, and with every part of the living body, 
than does any other organ ; and, in turn, every other 
internal organ, and every part of the living body, 
sympathize more directly and powerfully with the 
stomach than with any other organ. 

299. But notwithstanding the organs of animal life 
have very little direct sympathy with each other, yet 
inasmuch as they depend on the nerves of organic life 
which belong to the blood-vessels that enter them for 
their continual sustenance and healthy condition, they 
sympathize very directly, and, in a diseased state, very 
powerfully, with the internal organs, and particularly 
with the stomach. If the eyes, ears, hands, feet, or 
any other part belonging to animal life, be diseased, 
every disturbance, irritation, or oppression of the 
stomach, aggravates that disease ; and chronic indi- 
gestion always impairs the tone and functional power 
of the whole external skin, and indeed of the whole 
living system. Few thing^s, it is well known, will 
more speedily and completely prostrate the muscular 
powers of even the strongest men, than high irritation 
in the alimentary canal. On the other hand, the in- 
ternal organs sympathize very directly with those of 
animal life. The continued action of excessive cold 
upon the external skin, retards all the internal func- 
tions ; and so, also, the continued action of excessive 
heat on the external skin debilitates the stomach and 
other internal organs, and always tends to cause indi- 
gestion, pulmonary disease, etc. In short, every ex- 
ternal affection has some sympathetic influence on the 
internal organs, and especially the stomach and ali- 
mentary canal generally ; the liver, lungs, kidneys, 
etc., are also intimately involved in this sympathy. 
But of these reciprocal sympathies between the organs 
of organic and of animal life, perhaps the most pow- 
erful at all times is that which exists between the 
stomach and the brain. A severe blow upon the head 
will cause nausea and vomiting, and all degrees of ir- 
ritation in the brain proportionably affect the stomach; 
and, on the other hand, certain irritations of the stom- 
ach will cause vertigo of the brain, or a derangement 
of the functions of the brain, or even a total suspen- 
sion of its functional powers ; and all degrees of irri- 
tation in the stomach, which affect its general condi- 
tion, proportionably affect the brain. And let it be 
remembered also, that in all the sympathetic as well 
as idiopathic or original irritations of the stomach, the 
liver, intestinal tube, and other internal organs sym- 

300. This wonderful economy of sympathy, which, in 
a well regulated state of the living system^ is admirably 
adapted to the purposes of vitality, and is exceedingly 
conducive to the enjoyment of the animal, may, by 
long abuses of the system, be converted into the source 
of the most intolerable suffering. In a healthy state of' 
the system, if any improper substance be brought within 
the precincts of vital action, the part with which the 
substance comes in contact, perceiving, by its organic 
sensibility (296), the deleterious character of thesub. 
stance, gives alarm to its centre of perception and ac- 
tion, and that centre takes immediate measures, by 
increased secretion, etc., to shield its special domain 
from the pernicious effects of the substance. And if 
the quality and quantity of the substance be such m to 
endanger seriously the vital interests of the whole syi« 



tem, the special centre gires alarm to the great com- 
mon centre of organic life, and thence it is spread 
throughout the whole domain, and all parts sympa- 
thize with the suffering organ, and, hy a general con- 
sentaneousness of action, strive together to remove 
the offending cause ; and when the emergency is great, 
and the danger imminent, the agonizing energy of or- 
ganic life is poured upon those muscles of animal life 
concerned in respiration, and violent vomitings, etc., 
•nsue. In all these operations the organic instinct 
mcts determinately, and, as it were, rationally, with 
reference to a final cause of good, viz. the removal of 
the offending cause. But if the disturbing cause be 
too long continued, or too frequently repeated, the or- 
ganic sensibility of the part becomes diseased, and ex- 
cessive irritability is induced ; and if the part be an 
important one, such as the stomach or intestinal canal, 
the diseased irritability is soon propagated through. 
out the whole domain, and a highlv morbid sympathy 
is universally established. In sucn a state of things, 
the organic instincts when agonizing with irritating 
causes, frequently acts with most fearful insanity, 
pouring its misdirected energy on parts whose action 
cannot afford relief, and terrible spasms and general 
convulsions are produced. These effects are generally 
attributed to the irritations of the brain. But I am 
convinced that this is a capital pathological error, and 
that it has been the source of immense error and evil 
in therapeutics. The brain undoubtedly may be the 
primary seat of those irritations which cause spasms 
and convulsions, but this is not necessarily the 
case. Epileptic and other convulsive fits, and spas- 
modic affections, almost universally result from irrita- 
tions in the domain of organic life; and the alimentary 
canal is most generally the primary seat of those irrita- 
tions. When the irritations and convulsions are long 
continued, the brain becomes sympathetically involved, 
and often suffers most ruinously, even to the entire 
derangement or total abolition of its functions, and 
decay of its substance. Yet how often do we see the 
most terrible spasms and convulsions where there is 
not the slighest symptom of cerebral irritation ! pre- 
ying that the morbid irritations of the nerves of or- 
ganic life can be transmitted directly to the muscles 
of animal life, without the agency of the cerebro-spi- 
nal centre. The numerous branches which the gang. 
lions, and particularly the limiting ganglions on each 
side of the back-bone, send to the muscles of animal 
life (284), are probably the media through which the 
irritations are transmitted. 

301. The nerves of organic life, I have said (294), 
are, in a state of health, entirely destitute of animal 
sensibility, but as we have seen (296), they are en- 
dowed with an exquisite organic sensibility, which 
analifies them most perfectly for the performance of 
lieir constitutional functions in the living system ; 
and the complete integrity of those functions essenti- 
ally depends on the healthy properties of the nerves. 
But the organic sensibility of these nerves may, by 
continued or repeated irritation, become exceedingly 
morbid or diseased, and a preternatural irritability 
and diseased sympathy may be induced and perma- 
nently established. In this state of things, all the 
functions of organic life are necessarily impaired, and 
to an extent always proportionate to the degree of dis- 
eased irritability and sympathy of the nerves. The 
food is less perfectly digested in the stomach, the 
chyle is less perfectly elaborated, the blood necessarily 
becomes deteriorated, and the whole system, in every 
part and tissue, consequently suffers. By excessive 
and continued irritation, also, inflammation may be 
Induced, and the most painful sensibility developed 
In the nerves of organic life, so that the centre of ani- 
mal life will not only be conscious of the pain, but 
rder it to the part diseased ; the same as it does im- 
jnressions or affections of its own domain. This state 
cf things is not only distressing, but is always injuri* 

ous to the living system, and often imminently haz- 
ardous to life. When, therefore, we are conscious 
that we have a stomach or a liver, from any feeling 
in those organs, we may be certain that something is 
wrong. For, as I have already remarked, in a per- 
fectly healthy state of the system we have no conscious- 
ness of individual organs within us, and no other con- 
sciousness of the domain of organic life as a whole, 
than such as appertains to the general wants of the 
vital economy, which require the exercise of the vo- 
luntary powers in supplying food, drink, and air, and 
in the voluntary eliminations of the body. When the 
food is procured and masticated and swallowed, it has 
passed beyond the cognizance of animal life, and is 
given up to the operations and processes of the vege- 
table organs, to be converted into chyme ; from which 
is elaborated the chyle, the blood, the bone, the mus- 
cle, the nerve, etc., and all without the care or con- 
sciousness of the animal. 

303. Let us now, for a few minutes, contemplate 
the sympathetic relations between the nerves of or- 
ganic life and the mind. 

We have seen (218), that the great centre of organic 
life presides in a general manner over all the func- 
tions concerned in nourishing and sustaining the 
body; and consequently these functions are removed 
from the control of the will. The stomach, the 
liver, the heart, and all the other internal organs, 
regularly perform their functions without the agency, 
and beyond the direct control, of the will. 

Because it is the business of the voluntary powers 
to fulfil external relations, and to prevent the ingress 
of improper substances to the lungs and stomach, a 
wise and benevolent Creator has made the will, as 
it were, a warden to those important organs. Should 
we find ourselves surrounded by an offensive atmos- 
phere, or submerged in water, the will, by a direct 
control, can suspend respiration for a very short time ; 
and for similar reasons, it can exert its power directly 
on the apparatus of respiratory muscles, to accelerate 
their action. By a voluntary control of the respira- 
tory apparatus to a necessary extent, we are also en- 
abled to speak, sing, etc. Yet the function of respi- 
ration is properly an involuntary one, and is per- 
formed independently of the will. So in regard to 
the stomach ; the will must control the functions of 
chewing and swallowing the food, but the instant the 
act of swallowing is performed, the food is beyond 
the direct control of the will. 

303. Properly speaking, therefore, the mind cannot 
exert the power of the will directly on any organ 
strictly within the domain of organic life. The ordi- 
nary, calm, and gentle operations of the mind, have 
little if any effect upon the nerves of organic life. 
But when the exercises of the mind are intense and 
protracted, the whole domain of organic life sympa- 
thizes with the brain ; and when these exercises are 
of an excited and impassioned kind, the sympathetic 
influence is poured with considerable energy upon the 
nerves of organic life, and all the functions of that 
domain are more or less disturbed ; while, at the same 
time, a strong emotion or sensation of a peculiar kind 
is produced in the epigastric centre, usually referred 
to the heart ; but the stomach, more than any other 
or^an, is the true seat of it. Hence the function of 
this organ is more affected by mental influence than 
that of any other ; and, indeed, it is in a considerable 
measure through the stomach that the other organs 
are affected by mental influence. In all violent pas- 
sions, however, the whole domain of organic life 
seems to be, as it were, inundated by the lava of the 
mental volcano, and the actions of the several organs 
are convulsively accelerated or retarded to a most 
fearful and dangerous extent ; and in some instances, 
all the functions of life are suddenly arrested as by a 
lightning stroke, and death is instantaneously in- 
duced i 



304. All mental excitements, therefore^ are causes 
of some degree of disturbance to the nerves of orgranic 
life ; and when violent, and frequently repeated, they 
necessarily induce, and permanently establish, a mor. 
bid irritability and sympathy throughout the whole 
domain, generally involving also the brain and spinal 
marrow, and especially the brain. Functional aber. 
ration and derangement necessarily result from this 
state of things, leading to disease and change of struc- 
ture in the organs. 

305. On the other hand, the mind sympathizes in 
the most delicate and powerful manner with the nerves 
of organic life, in all their general affections and 
conditions. When this system of nerves is in perfect 
health, and under the influence of appropriate stimuli 
— such as proper air in the lungs, proper food in the 
stomach, proper chyle in the lacteals, proper blood in 
the arteries, etc., — ^the instinctive wants of the sys- 
tem are satisfied, every organ performs its function 
with tone and alacrity, and a delightful communion 
of sympathy pervades the whole domain. In all this 
there is no local feeling, no animal perception of a 
distinct sensation in any particular part ; nay, indeed, 
there is not the least animal consciousness of any in- 
ternal organ. Without being conscious whence it 
comes, or on what it depends, the animal is simply 
conscious of a general, and, as it were, spiritual joy. 

And in this consciousness the playful lamb 

Skips with delight and gambols round its dam ; 

The calf and colt, from their confinement freed. 

Stretch their young limbs and oound along the mead; 

The noble horse, with wildly flowing mane 

And wide-stretched nostrils, gallops o'er the plain ; 

Lifts high his head, as of his freedom proud, 

Snufik the pure breexe, and snorts his joy aloud. 

And, in this consciousness, with infant glee, 

The tottering child plavs round the mother's knee. 

The older sister, though oft chid as rude. 

Yields to the spirit of her romping mood; 

With her loved brother seeks the open air. 

And they like lambs, run, leap, and frolic there. 

E'en fiill-grown man, though crippled, blighted, cursed. 

By evil habits long and fondly nursed, 

In healthier moments still doth often feel 

Something of this pure spirit o'er hit bosom steal I 

The mind, in all its faculties and operations, feels 
the bland exhilaration, but it is not conscious of its 
nature, nor of its source. The thoughts flow with 
greater ease and increased energy, the imagination 
becomes more vivid and vigorous, and the memorv 
more clear and active. But the mind is not at all 
conscious that this state of things is in any degree 
connected with the condition of the body; on the 
contrary, it thinks that the exhilaration is aboriginally 
and purely mental, and that the pleasurable feeling 
results entirely from its own felicitous exercises. This 
delightful sympathy between the nervous system of 
organic life and the mind may be preserved through 
life ; and were all the laws of constitution and rela- 
tion which our benevolent Creator has established in 
our nature, properly obeyed, it would be so. While 
the nerves of organic life are preserved in a perfectly 
healthy state, the mind is habitually serene and 
cheerful, as in healthy childhood. Moral causes may 
give it pain, but as soon as the direct action of those 
causes ceases, it springs elastic from the oppression, 
like that of a little child which turns from the chid- 
ings or chastisements of a parent, to forget its sorrows, 
and to break into the smiles of its revived enjoyment, 
before the tears are dried from its cheek. But when, 
by the continued irritations of the stomach and other 
organs, the organic sensibility of the nerves becomes 
diseased, and a morbid irritability and sympathy are 
gradually induced and permanently established, the 
mind, sympathizing with the nerves, and yet without 
the consciousness of that sympathy, gradually loses 
its habitual serenity, and by degrees becomes snroud- 
ed, first, in the occasional and then the more constant 
pensiveness of early youth, and this is followed by 
the darker shades of youthful discontent ; a deep, 

continual restlessness ! We are unhappy, yet we 
know not why. We long for relief, but we know not 
what. We would go, but we know not where ! We 
would cease to be what we are, yet we know not what 
we would be. This sickly sentimentality tends 
always to a more confirmed and painful melancholy, 
from which we only find occasional relief in the in- 
toxications of a misguided world ; and too frequently 
the very means of our relief, serve to aggravate our 
disease, till we become completely wrapped in the 
black and cheerless pall of unutterable despondency. 
And even they who seek relief in the faith which looks 
forward to a better world, too often have little other 
enjoyment of their existence than that which arises 
from the hope of what they shall be beyond the 
grave ; and this is often torn from them by morbid 
doubts and fears. In all these painful sympathies, 
as in the pleasmable ones, the mind has no conscious- 
ness that it sympathizes with the body, but fully 
believes that all its sufferings are purely of a mental 
and moral nature ; and it seeks and fixes on some 
object which it believes to be the cause of all its 
misery. The dread of becoming poor, of losing friends 
or reputation, or some other imaginary evil, haunts 
the mind thus laboring under the influence of a dis- 
eased body, perhaps to utter madness ; and too fre- 
quently the miserable victim rushes from the world 
in the anguish of insupportable despair. 

306. Such are the direct relations between the mind 
and the nerves of organic life. The indirect relations 
are numerous and important, many of which I shall 
explain hereafter. All those predispositions and 
peculiarities which we call hereditary, are transmitted 
from parent to child through the medium of this sys- 
tem of nerves, such as temperament, predisposition to 
consumption, dyspepsy, and all other diseases of the 
body ; and also the mental and moral predispositions : 
for I shall show hereafter, that, admitting all that 
Gall and Spurzheim claim concerning the organiza- 
tion of the brain and its relations to the mind, still 
the nerves of organic life are the media through which 
all cerebral peculiarities are transmitted from parent 
to child. 

307. Like the other solids which I have de8cribe49 
all the nerves of the body are much more soft and 
pulpy in early life than at a later period. In ad- 
vanced age they usually become much drier, smaller, 
and harder. Ordinarily, in civic life, the internal 
ganglions with their cords begin to diminish in size^ 
and to become paler, drier, and harder, about the 
fortieth year ; but the period is greatly varied by the 
habits of the individual. 


The cellular, muscular, and nerrous tissues, and their vital pro- 
petties, compose the organs, and endow them with fiuictioBal 
pewer— Definition of tissue, organ, vessels, viscera, vaaenlor 
system^ capillary system, Auction, vital economy, etc. — Chaagv 
of matter in organixedbodiet— They are oiganiced and endowed 
accordingly — ^V^etable bodies, how nourished and organised- 
Animal bodies, how nourished and organised — Grand f\Bn^on 
of the alimentary cavity — llasticatory organs, jaws, teeth, 
tongue, etc.; their development, character, and functions — ^Th* 
fibrous, serous, and mucous membranes; their situation and 
office — ^The anatomy, disposition, and functions of the skin and 
mucous membrane particularly described— Simple afeMMrbentfl 
and exhalants— mucous follicles and glands — Mucous mem- 
brane forming the oesophagus, stomach, and intestines-— Salivary 
glands, liver, pancreas, kidneys, etc. — Muscles of the alimentary 
canal; their arrangement, etc.— The peritoneal ooat— Nenres 
of alimentary canal, etc. — Respiratory apparatus — the structure 
and Auictional purposes of the several parta— larynx, windpipe, 
lungs, diaphragm, ribt, etc— Organs of circulation— henC, 
arteries, veins, capillaries; their distribution, etc.— The portal 
system and the spleen — ^The lymphatics; their structure, situa- 
tion, and office— The lacteals— Circulating forces— Propelling 
power of the heart, etc.— General law of vital action and ex- 
penditure, and flow of arterial blood — ^Local increase of cirenla- 
tion— Organs of taste, smell, hearing, and sight— Hair aod 



308. Having given a general description of the 
oellulary muscular, and nervous tissues, in their separ. 
ate forms, and having described their vital properties, 
and presented a general vietv of the disposition of 
these three elementary tissues in the formation of the 
living animal body, I now proceed, after a very brief 
recapitulation, to the consideration of the structure of 
the particular organs. 

209, The cellular tissue, I have said (158), is the 
lowest order of animal structure. It pervades every 
part of the body, constitutes the general frame of 
every organ, connects all the tissues, and binds all 
parts together (168 — 171). Its property, which is 
called vita], because it is much greater in the living 
than in the dead body, is elasticity. 

310. The muscular tissue (159) is a higher order of 
animal structure than the cellular. Its most import- 
ant property in the vital economy is contractility. 
This is the element of all voluntary motion, and of 
most, if not all, positive involuntary motion, in the 
living body. The muscles are divided into those of 
voluntary and those of involuntary motion (194), or 
those of animal and those of organic life. The former 
being mostly attached to the bones, and lying princi- 
pally on the outside of the frame, and around the- 
bones of the upper and lower limbs (189); and the 
latter being situated in the hollow organs composing 
the respiratory, digestive, and circulatory apparatuses. 
^ 311. The nervous tissue, with its important proper- 
ties, relations, and sympathies, I have described at 
large in my last two lectures (160—165, and 202— 

312. These three general tissues, I have said (167), 
together with the more solid matter of the bones, 
compose all the organs and parts of the animal sys- 
tem, and in entering into the texture of the several 
organs, each tissue carries with it, and retains during 
life and health, its own peculiar vital properties ; and 
these properties, viz., cellular elasticity, muscular sus" 
eepObilitjf and contractility^ and nervous and sensorial 
p&weTf together with the vital affinities, which are under 
the control of the nervous power, constitute the vital 
forces of the organic economy, and the functional powers 
of the organs. 

313. Though these three general kinds of animal 
structure are, in the language of modern physiology, 
called tissues, yet, strictly speaking, a tissue is a par- 
ticular arrangement of fibres or filaments, in the for- 
mation of an organ. * An organ is a compound body, 
consisting of a specific arrangement of different tis- 
sues.' The internal organs are, in the descriptions of 
anatomy and physiology, divided into vessels and 
ftiseera. The vessels, such as the arteries, veins, 
lymphatics, etc., are called the vascular system ; and 
the minute extremities of the arteries and veins, 
wbiehy together with the lymphatics, compose a large 
proportion of the bulk of the whole body, are called 
ibm capUkay ^tem. The stomach, liver, pancreas, 
sploen^ intestinal tube, etc., are collectively called t]ie 
ffiecira, or singly a viscus. A function is the office 
whSflh an organ performs. And the vital economy 
consists of the general co-operation of the whole 
ass^nblage of living organs, in the performance of 
th^ several functions, to one grand result, viz., the 
susfeiutfioe of the body in all its organization and in 
all -Its functional powers and operations. With these 
T^onpituUitions and explanations, we are now prepared 
to entfr npon the consideration of the structure of 
pwrlieolmr organs. 

Sl|i We have seen that all living bodies are formed 
frmd die common inorganic matter of the world (49, 
llif. IIB); that the matter composing organized 
bo«s is brou|fht into the organic arrangement apd 
stitietiirea by vital forces acting in and by living or. 
gaQs^ which overcome and subdue the inorganic affi- 
nities (ISI), and hold the organized matter, as it 
were, in reluctant obedience to vital power; and 

hence the matter composing living bodies has always 
a tendency to yield to the affinities, and to return to 
the more simple and primitive forms of inorganic mat- 
ter. Hence, also, as a general fact, matter is less 
permanent in organic than in inorganic forms (133). 
It does not remain permanently in organized struc- 
ture during the life of the body, but, particle by par-, 
tide, is continually giving place to new matter, so 
that, in the course of a few years, all the matter in 
the human body undergoes a change. The two great 
processes of composition and decomposition, of incor- 
poration and elimination, are therefore continually 
going on in the living body. Foreign matter, on the 
one hand, is continually assimilated and incorporated ; 
and organized matter, on the other hand, is continu- 
ally decomposed and eliminated. All living bodies 
are, therefore, adapted in their organization to this 
condition. They have organs which act on foreign 
matter, and assimilate it to their own nature, and 
organs which distribute the assimilated matter to 
every part of the organic system, and organs which 
convert this matter into the various structures and 
substances of the body, and organs which decompose 
these structures and substances, and organs which 
convey the worn out and excrementitious matter 
from the vital domain. 

315. The particular organization of the different 
species of living bodies, corresponds with the charac- 
ter and condition of the foreign matter on which 
they subsist. 

316. Vegetable bodies are nourished entirely by 
aqueous and gaseous forms of matter. The former, 
as a general fact, they derive from the bosom of the 
earth, the latter from' the atmosphere (208). Hence 
they require no masticatory organs, and no internal 
cavity to contain their food, and to reduce it to the 
fluid state ; but they send their roots into the earth, 
to imbibe its moisture, and extend their trunk and 
branches, and spread out their leaves in the atmos- 
phere, to inspire its gases ; and remain through life 
fixed to the spot from which they spring, elaborating 
all the varieties of vegetable substances from inor- 
ganic matter, and thus preparing food for a higher 
order of living bodies. But animal bodies, being 
nourished by substances whose character and condi- 
tion render voluntary powers and locomotion neces- 
sary (293), require an internal cavity or sack to con- 
tain and digest their food, and prepare it for the ac- 
tion of those organs which correspond with the roots 
of plants. And hence, every animal, from the zoo- 
phyte to man, has an internal cavity for the reception 
and digestion of its food ; and this is one of the grand 
peculiarities which distinguish animals from plants. 


317* But though all animals are alike in possessing 
an internal cavity for the reception and digestion of 
their food, yet they differ most widely in the con- 
struction, capacity, and general arrangement of their 
alimentary apparatus ; each species being adapted in 
its organization to its appropriate kind of aliment. 

318. In some, the alimentary organization consists 
of a simple sack, with a single aperture, through 
which every thing it receives and evacuates has its 
ingress and egress. In others, it consists of a tube or 
can^, of nearly equal size in all its parts, extending 
directly from the mouth to the posterior end of the 
trunk, and having an aperture for the reception of 
food, and one for the evacuation of excrementitious 
matter. In others, again, the alimentary tube is con- 
volved or folded, so that its length is several times 
that of the body, and portions of it are greatly en- 
larged, so as to form what are called the stomach, the 
colon, etc. 

319. In those animals that subsist on food which 
is rapidly digested, and which requires a quick pas- 
sage, the stomach is simple, and the alimentary tube 



etimpai'ali7ely short, and ju general capacity ii com- 
paratively ; whUe in thoie that feed on sub^ 
stances which cont^Jn little nutriment, &nd are slowly 
dige^^ied, the canal h cnniparatirely mueb longer, and 
either has sereral capacious enlargements, or the 
itomiicii and colon are eo constructed as to retain 
thetr contents a con^iiderable time. In a third gene- 
r&i cla$» of animals, which inihsist on & more nutri- 
iJouti aliment, snch as the farinacious seedi, graioA^ 
roots, etc., and variouii fruits^ the alimentary Cube, &b 
a general rule, is comparatlirely long€rr than that of 
the Erst daiis just descrihe^, and shorter thaiv that of 
the second ; but ita general calibre or capacity i& oom- 
par^cively targe, and the stomach aud colon are Etted 
for a slow passage of their contents. 

320. But whether the alimentary cavity he a sim- 
ple sack, or & straight tuhe» or a codifolved canal with 
one or many enlargements, its grand fuuctmo is al- 
ways the same, viz., converting the food into that p^r. 
tiai/y assimiiated subsiance which u eail^d ehume, and 
preseniinff ths chyme io those organs which elaborate the 
chyh from U^ and c&n^je^ing the fecal matter from the 

321 , In regard to other portions of the alimentary 
apfjaratuB, animals differ as widely as they do in re- 
spect to the inttinial cjivity, Sorae simply Jmhibe a 
liquid aliment ; some swallow substances of more corj^ 
sistency, which readHy disaoke lO the cavity, without 
any mechanical trituration or breaking down ; others 
swallow harder substances, which are triturated or 
mashed by an internal apparatus; and others have 
org'An^ in the oral cavity or mouth, with which they 
masttcate their food. In respect to the masticatory 
organs, atitmala differ again very considerably. Some 
are fitted to tear and cut fle:bh into amail majises, 
others to crop the grass and grind the woody fibre, 
and others to cut and raash the bulbous roots or fruits 
or other substances which constitute the appropriate 
aliment of the species. 

323. The alimentary apparatus of man consists of 
masticatory organs, a meatpipe, a stomach, an ali^ 
men tar y tube several times the length of the bodyj 
together with various glands, vessels, etc. 


323. The oral cavity is formed by the hones of the 
head and face, united by cartitages, and bound toge^ 
ther by ligaments, and invested by muscles and mem. 
branes. The tipper jaw, with all the other bones of 
the face, except the lower jaw, is firmly attacked to 
the skull, and only tnoves with the whole head* The 
lower jaw is a separate bone, having 
somewhat the form of a horseshoe^ and is 
attached to the tecnporal bones of the 
skull by a peculiar joint, which admits 
of a free backwards and forwards, or tip 
and down motion, and also a considerable 
extent of lateral motion. These motions 
are performed in chewing, talking, etc^ 
by several pairs of appropriate muscles. 
Each jaw is composed of an external and 
internal plate of dense bone, and an in- 
termediate bony substance which is ex- 
ceedingly spongy. la this spongy struc^ 
ture are the cavities which contain the 
roots of the teeth. Before the teeth are 
formed, small rounded sacks are produced, 
in the places of the teethe These sacks 
are formed of two membranes : an outer 
one, whlcb adheres very closely to the 
gums, and is destined to surround the 
roots of the teeth as a permanent perioB« 
tium ; and an Inner one^ on which are 
dispersed the vessels and nerves destined 
to form the tooth, and to supply its tex- 
ture. Between these two membranes is a 
small quantity of serons ^uid. In dtie tim^ 

a soH; gelatinous pulp rises from the base of the internal 
membrane, and gradually assumes the exact shape 
of the tooth ; and, at the same time, numerous nerves 
and vessels are given off from the inner membrane, 
and distributed to the pulp or germ, which is itself 
enveloped by a thin vascular membrane. These ves- 
sels soon commence the work of forming the bony 
substance of the tooth. In the single teetht the pro- 
cess of ossification begins in a single point at the top* 
In the double teeth, it begins simultaneously at the 
several corners or elevations at the top, A thin shell 
is first formed on the outside, and then layer after 
layer is added inwardly, gradually diminishing the 
cavity, and reducing the size of the pulp. When the 
crown of the tooth is couNiderahly advanced, the pulp 
throws one, two, or three branches downwards, ac- 
cording to the number of routs which tbe tootb has, 
and the root or roots are formed in the same manner 
as the crown is. In the mean time, the vascular 
membrane, which envelops the germ, and which sur- 
rotinds the crown of the tooth, commences the secre- 
tion of a fiuid, which gradually hardens into the ena- 
meh When it becomes necessary for the toolh to 
emerge from the gum, a set of vessels called absorb- 
ents, which F shall soon describe (385), begin their 
operatiotis, and remove before the rising tooth al! the 
superinctimbent substance. The tooth, at length, 
lifts its body above the gnm, which is a dense snb* 
stance composed of the cellular tissue, and which sur- 
rounds the neck of each tooth, and covers the edges 
of the jaw- hones, affording a firm support to the 

334. The two inner front teeth in the lower jaw 
are generally the first which make their appearance, 
about the seventh month after birth. These are 
soon followed by the two corresponding ones in the 
upper jaw ; and to these succeed the two outer front 
teeth of each jaw j and then follow the first molar or 
double teeth of the under and upper jaws; and then 
the eye or corner teeth ; and lastly the second or pos- 
terior double teeth appear, i^o that, in the course of 
three years, the whole twenty deciduous or temporary 
teeth make their appearance (Fig. 17)< 

325. Vt^'hen the pulp or germ which produces the 
temporary teeth in the manner I have described, is 
fully developed, and about to commence its process of 
ossification, it gives off a very small germ or sac, 
formed precisely like itself in its first state, and ad- 
hering to it by a minute branch or cord» For this 
new germ, a cavity is prepared by the absorbents, in 

Fig. 17. 

Tht tiaiportiy testt, showlftK tlie g»riiii of tlifl pcmiiiiKtn tt.aih 



the spongy part of the jaw bone, where it lies care- 
fully and securely deposited till the Jaws are suffi. 
ciently lengthened and enlarged for the development 
of the second or permanent teeth (Fig. 17). In the 
present general state of the human constitution, the 
process of second dentition ordinarily commences 
about the sixth or seventh year of life. The perma- 
nent teeth are developed in precisely the same man- 
ner, and appear in nearly the same order, as the first 
teeth ; and as they advance in development, the roots 
of the first teeth in a perfectly normal and healthy 
state of the system are gradually absorbed and car- 
ried awav, till nothing is left but the part above the 
gums, which becomes very loo&e, and is easily re- 
moved. Sometimes, however, in the present physio- 
logical condition of man, it becomes necessary to re- 
move a temporary tooth by violence, before its root 
is absorbed away. 

326. The last of the permanent teeth do not usually 
appear till about the twentieth year of life, and they 
are therefore called the wisdom teeth. These are 
double teeth, and are situated in the back part of the 
jaws. When all the permanent teeth are developed, 
there are two front, one corner, and five cheek teeth, 
in each half of both jaws, making in the whole thirty 
two. The four front teeth in each jaw have single 
roots, and chisel-shaped crowns for cutting, and are 
called the incisors (Fig. 18, No. 1, 2). Tl^e corner 

Fig. 18. 

teeth, betireen the front and cheek teeth, are the 
firtt step of transition from the chisel-shaped cutters 
to the square-crowned mashers. They, tnerefore, of 
naoetsity, take more of the rounded and pointed shape 
than the front teeth. They have each but one root, 
which is however longer than those of the front and 
eheek teeth. Their crowns, as it were, combine the 

forms of the front teeth and the first of the cheek 
teeth, being somewhat flattened like the front, and 
yet approaching to a single point like one of the ele- 
vations of the first cheek teeth (Fig. 18, No. 3). They 
are therefore called the cuspids or spear-shaped teeth, 
but more commonly the eye teeth. The first two 
cheek teeth on each side and in both jaws, have the 
form of two corner teeth united by their inner faces. 
They have each a single root, but it is generally some- 
what flattened and grooved like two roots united, and 
in some instances it divides into two. Their crowns 
approach to the square form, or oblong square, and 
have two elevations at the top, the one on the exte- 
rior, and the other on the interior face, appearing 
like the points of the comer teeth ; and hence they 
are called the bicuspids, or two-pointed teeth (Fig. 18, 
No. 4, 5). The three remaining cheek teeth, on each 
side, and in both jaws, have the form of two bicus- 
pids, or four comer teeth united. Those of the up- 
per jaw have three roots, and in some rare cases four, 
which are considerably shorter and much more diverg- 
ent or spreading than those of the under jaw, to 
avoid penetrating the cavities in the upper jaw be- 
longing to the olfactory apparatus (399), and at the 
same time to give sufficient firmness to the teeth. 
The crowns of all these teeth are large and nearly 
square, with four or five slight elevations on the 
grinding or mashing face. These are called the mo- 
lares or grinders (Fig. 18, No. 6, 7, 8). 

327. The bony substance of the teeth is consider- 
ably harder than that of the other bones of the body, 
and contains less gelatinous matter (169). The ena- 
mel which covers the bony substance of the crown or 
body of each tooth, and extends down to the edge of 
the g^m, is far the hardest substance in the living 
body. It is indeed a species of organic chrystalixation. 
This substance does not appear to be in any manner 
nourished or reproduced in man, after the tooth is 
fully developed ; but, being extremely hard or dense, 
it sustains the friction of mastication for many years, 
without being worn through. The internal cavity of 
the teeth occupied by the pulp is never wholly filled 
up, but it is considerably smaller in advanced life 
than it is in youth (fig. 19). It continues by small 

Fig. 19. 

canals through each root; and at these canals the 
vessels and nerves of the teeth enter (254) ; and after 
ramifying upon the membrane that lines the cavity 
(323), they are distributed to the bony substance, 
penetrating to the enamel ; but they do not enter this 
last named substance (fig. 20). These vessels and 
nerves are largest, and pervade the bony substance of 
the tooth most extensively in early life. They gradu- 
ally diminish in size, and become obliterated in their 
extremities, as life advances, and recude from the sur- 
face inwardly towards the central cavity. MHien the 
habits of life are not in strict accordance with the 
physiological laws of the body, the canals in the roots 
of the teeth often entirely close in old age, and the 
teeth are wholly cut off from vital sustenance, and 
then they soon become loose, and drop out of the jawt^ 
or their roots are removed by the abtorbenta. 



328, In the human head, the front teeth &re in* 
tended to ctit the fcmd into small maiseB^ corvvenient 
£or the action of tha cheek teeth, which are deBigned 
to maah or grind it finel^j before it i& swallowed. 
This procesiA is called tnasti cation ; and while it is 
going on, other organs co-operate to prepare the food 
for deglutition, and to commence the proce&s of aasi* 

Fig- 20. 

Tlni ptrm^i Lttthj niiowiug the cptrance of lh» nerres Into diD cudE of the roots 

329. The tongue T hd^rdly wetd deacrlhe. It lit 
composed of many different paifs of mnsdes, which 
render tt capable of acting in every direction, and m 
almost every manner ; and is coFererl by the mncous 
membrane, which lines the mouth (287)- It ASJsists 
in masticating the fo'jd, by contlmiaHy throwing Jt 
between the grinders of tlie tipper and lower jawi. 
It also assists in the act of swallowing tt, in a manner 
I shall describe when I come to speak more particu- 
larly of the functions of these parts* 


330, 1 hare already described three general kinds 
of membranes* I. The fibrous (1G3), which every- 
where surrounds the bone«, cartilages, a ltd tendons ; 
lines the spinal canal, the cavity of the skull, etc, 
3. The serous (176), which lliies the closed caWties, 
such as the thorax and abdomen, and surrounds all 
the organs of those cavities (fig, 32), 3. The mem- 
brane ir Li ch covers the whole external surface of the 
body like a sac* and passing over the lips and up the 
nostrils, lines the mouth, nasal cavities, throat, wind- 
pipe, lungs J meat pipe, stom ^ch, alimentary tube, and 
every other internal cavity which has an opening 
outwardt or which by a mouth or canal communicates 
with the external world (SflJ). The portion of this 
membrane which covers the external surface, I have 
satd (289), is called the sxrw, that lining the internal 
cavities is called the Mucoua »tE>rBRA>r£, The 
general office of the 6brous and serous membranes is 
to cover and line the parts to which they are appro- 
priated, and in some measure to keep them in their 
proper positions, and to ftirnish the cavities which 
they line with a serous, glairy fluid, bv which the 
parts that move upon each other are moistened and 
lubricated ; and also to absorb ivhatever fluids may 

he introduced into these cavities.* For this kind of 
exhalation and absorption, they require nothing' more 
than the minute extremities of the artertes and reint, 
and the lymphatics. But the general office of the skin 
and mucous membrane is much more diversilied and 
complicated. This extended membrane, as I have 
stated ('^88), constitutes the general confines of the 
vital domain, and is constructed with reference to all 
the relations which that domain 
holds to the external world ; and 
through it, must pass, by the ao- 
tion of living organs, every thing 
that enters into that dooiain, or 
egresses from it. If pure aque*- 
ous fluid is required to enter that 
domain with little or no change^ 
appropriate organs in this mem^ 
brane must absorb and convoy il 
thither. If there be an excess of 
aqueous matter within the vital 
domain, this membrane must fur- 
nish organs to exhale or eliminate 
It from the system. If nutrient 
matter is to enter the domain of 
life, appropriate organs in this 
membrane musi elaborate it from 
the con cents of the alimentary oa- 
vity^ by an assimilating process 
peculiar to themselves, and, as it 
were, hand it over to other func- 
tionaries of the system, to be sub- 
jected to other processes, and fi- 
nal ty disposed of for the general 
good of the body. If miK'iiagin- 
0U5 and oleaginous substances are 
to be secreted from the vital do- 
main, to lubHcate the exterior 
surface of this membrane* and 
protect its myriads of delicat« 
little organs, and preserve them 
in proper conditions to perform 
their functions, or to oil the 
externa! surface of the body, to preserve the skin 
from the injurious action of various external 
agentSy other appropriate organs in this membrane 
must secrete those substances. And if substances of 
a yet more exalted or complicated character, such M 
the saliva^ the pancreatic fluid, the bile, etc, are to 
be secreted either for the purposet of the vital eco- 
nomy in carrying on its assimilating processes, or for 
the sake of separatitig e^crementitioui matter from 
the fluids of the system, and eliminating it from the 
vital domain, this mem bran* must furnish the organs 
for the performance of these various and wonderful 


33 L In giving a general description of the skin and 
mucous membrane (287), I said that countless num- 
bers of the almost inconceivably minute terrninationi 
of capillary vessels of the sanguifi?rous and lymphatic 
systems, pass through the meshes of this membrane, 
and form a close web or plexus upon its exterior sur- 
face. Some of these minute vessels thus situated, are 
employed in their simple form in absorbing such aque- 
ous and other substances as are at any time permitted 
to past into the vital domain with little or no asstmi- 
lating change. These pervade the whole external ojid 
intertial membrane, but mostly abound in the mucoui 
membrane of the alimentary and respiratory cavities, 
and especially in the stomach and alimentary tube. 
Others, again, are employed in their simple form, in 
throwing off or eliminating like substances from the 
system in the state of vapor and of sensible fluids, etc 

* It U not 4 fettled polat, irhslhef the ^brous membTaiie in any 
titiiAdoa pcrfomu theu f Liactliiii« of secretin «iid sbtcivptiiiflt. 



ThtMe also peirade the whole ittembrane, but mostly 
abound in the lungs and external skin. Another set 
of these vessels are employed in their simple form, in 
secreting the nutrient matter by which the system is 
tttstain^.* These innumerably abound in the ali- 
m^ntary cavity, and especially in the small intestines. 
It is contended also by some physiologists, that or. 
MIS capable of performing this office exist in the 
luttgB and external skin ; and various experiments 
have been made, and anecdotes told, to prove that 
Imager may be appeased, and nutrition to some extent 
sustained, by the absorption of these surfaces ; but 
nMhing conclusive or satisfactory has been accom. 
plished ; and the utmost that can be affirmed is the 
possibility of a vicarious function of this kind, to some 
extent ; but this is not a normal function of the parts. 
832. In regard to the solvent fluid of the stomach, 
it is not yet ascertained whether it is secreted by some 
of these little vessels, in their simple form, or in their 
more complicated glandular arrangement. It is com- 
nion for writers on physiology to speak of the glandt 
which secrete the gastric juice, but the existence of 
tfaeae glands has never been demonstrated. 


333. The remaining functions belonging to, or im- 
mediately connected with, the g^eat enveloping and 
limiting membrane, appear to be performed by more 
complicated organs ; and yet, when thoroughly ana- 
lysed, they are found to be scarcely less simple than 
tnose described. The glandular follicles are the sim. 
plest kind of these organs. These are little bottle-sha- 
pad sacs imbedded in the substance of the membrane, 
with their mouths opening on its surface. The mem. 
braiie continues into these mouths, and lines the inter. 
nal cavities of the sacs ; or, in other words, the sacs 
are formed by the membrane itself, and supplied with 
nnlberons nerves and blood .vessds, and appear to 
possess a contractile tissue, by which they are enabled, 
ftt any time, to expel their contents. These abound 
in every part of the membrane, but cluster more nu- 
merously in some parts than in others, as the wants 
of the organic economy demand. Though apparently 
similar in their anatomical structure, they differ very 
considerably in the character of their functions. 
Some of them secrete the mucus which everywhere 
lubricates the membrane, and imbeds and protects its 
delicate nerves and vessels (287). Others, situated 
en the external surface of the body, secrete the unctu. 
ous matter which oils the skin ; of these sebaceous 
follicles there are said to be not lesR than a hundred 
and twenty millions : others, situated in the exterior 
caviticH of the ears, secrete the cerumen or wax of 
those cavities. Whether the coloring matter of the 
skin is a distinct secretion, by a special set of organs, 
or whether it is an effect of the action of light and 
heat and perhaps the oxygen of the atmosphere upon 
the mucous coat, is yet an unsettled point. 

334. The next form of a gland is still more compli. 
cated and much more extensive. Instead of the little 
sacs which I have just described, the membrane 
Ibrms a tube like the barrel of a small ^uill, and this 
tube, like the main stem of a shrub, gives off many 
branches, and each of these branches divides into a 
yery great number of twigs, and these are all hollow 
and formed by the same continuous mucous mem- 
brane ; so that all the minute hollow twigs open into 
the hollow branches, and all the hollow branches 
open into the hollow stem or main tube, and this 
opens upon the face of the great membrane. This 
ramified tube or duct is more or less extensive ac 
cording to the size of the gland, and the particular 
character of its function. But whether more or less 

* This process is by all writers on physiology called ' dbiorhing* 
but with utter impropriety. The iketeals no more absorb the 
chyle than the liver absorbs the bile, as will be shown hereafter 

extensive, it only differs from the Kttle sacs in shape 
and extensiveness. To complete the structure and 
functional capacity of the gland, an artery advances 
to the main tube, and suddenly divides into a great 
number of branches, and each of its branches into an 
immense number of twigs (fig. 21), and these minute 

Pig. 21. 

An artery of a gland dissected out. 

twigs terminate in the membrane which forms the 
hollow twigs and branches of the tube or duct ; and 
where thetse arterial twigs terminate, an equal num. 
her of venous twigs arise, which run together and 
form branches, and these run together and form the 
venous trunk or trunks of the gland, corresponding 
in ramification with the artery, but generally some- 
what greater in capacity, and passing from the gland 
by the side of the artery. With these vessels, which 
almost form a dense plexus, are also associated a great 
number uf lymphatic vesf^els ; and all these capillary 
arteries, veina, and lymphatics, are largely supplied 
with nerves of organic life (231), and intimately wo- 
ven together into a single organ, by a delicate cellu- 
lar tissue ; and, finally, the whole are enveloped in 
a serouH membrane, and thus the gland is completed 
(fig. 22). Some of the glands are provided with a 
membranous sac, which is also lined with the mucous 
membrane, and in which the secreted fluid or sub- 
stance is deposited for a time. 

Fig. 22. 

A gland, a a, with its excretory duct, c, and branches, h, 

335. This is a greneral description of what are called 
the conglomerate glands, such as the salivary glands, 
the pancreas, the liver, etc. In one important respect, 
however, the structure of the liver differs from that 
of other glands. This peculiarity I shall notice when 
I come to speak of its particular functions (381). But 
as a general statement of this class of glands, the ar- 
teries pour their blood into their myriads of minute 



tTvigs, which terminate in the mucoiiB Diembrane ilitt 
furtns ibe halJuw twigs and branches of the main tube 
or duct of the gland, and there the peculiar secretion 
of the ^land takes place, in a manner of which we are 
totally l^oraint. AIL we can say ia, that it U tin 
eFect of vitality, which seems in niany instances ac- 
tually ta posiiesa the power of transmuting one sub- 
stance into another (51) ; for many of the serretiona 
are totally unlike any thing to be found in the blond 
from which they are iecre£«4. The blood thrown 
into these vessels, which ii not employed in the secre- 
tion, b^ooies changed in its character by the process, 
ftnd m taken up by the venous captUarJeSf and carried 
off into the general rettirning circulation. The office 
of the lynipiatic vessels in these glands is not fully 
ascertained, but it is supposed to be the absorption of 
such substances as ought not to past into the secre- 
tion, nor to be carried off to the heart unchanged, in 
the vetioua blood. These substances mar be impuri- 
ties brought into the gland in the bh>od, or extrava- 
aated Buids, or the decomposed matter, or the lymph 
of the gland ; and^ in some cases, the iymphatics are 
supposed to absorb the more aqueouji parts of the se- 
cretion itself. These glands are situated in different 
parts of the body, according to the wants of the vital 
economy^ A considerable number of them, however, 
appertain to the alimentary cavity, and constitute a 
portion of the alimentary apparatus. It may, there- 
fore^ almost be said, that the great envelouing and 
limiting membrane which covers the external surface 
of the body, and lines all the open cavicJeSj is one ex- 
tended and complicated organ of secretion and excre- 
tluti, of absorption and of depuration* 

336, The external skin^ I have said, is covered 
everywhere by a thin membranous form of borny 
matter, called the cuticle or epidermis (207) i nnd 
■oine anatomists say that this epidermis extends over 
the whole mucous membrane. Dr. Homer, of Phila- 
ddphia, assures us that he has fully demonstrated its 
existence in the small intestine, and he therefore con- 
cludes that it pervades the whole alimentary cavity*" 
How the substances which en lent- or pass from 
the vital domain, get through the epidermis 
where it does exist, in a question much dis. 
puted. Some physiologists say that there are 
myriads of pores in the epidermis of the ex- 
ternal skin, through which the perspired 
fluids, etc., pass; while others conliidently 
deny the existence of a single one of these 
pores, and affirm that whatever passes through 
the epidermis, does so b^ a kind of infiltra* 
tion; and this, they think, ii fuUy proved 
by the fact, tbitt when a blister is raised upon 
the skin, the serum which accumulates under 
the epidermis do^s ni>t escape, as it would if 
there were uumerous pii<r^ through which it 
could paiw- But this seems to prove tot) much ; 
for it equally pr-ives the imperviousness of the 
cuticle by ik hit ration. Dr» Horner says he 
found it "wholly impervious to the air, with 
which he inflated it, in a section of the intes- 
tine. The troth, however, seems to me to 
b« most probably this : when the cuticle or 
epidermis is in its proper place, and holds its 
proper relation to the subjacent vessels and 
tissues, It presents openings to the moutlis of 
those vessels, through which they pour out, 
or drink in, such substances as they give or 
Uhe; but when it ia raised up, and separ- 
ated from its proper place and connexion, 
either by a serous fluid or by air^ those open- 
ings, from the peculiar construction of the 
parts hv which they are formed, become per- 
fectly closed^ and render the cuticle wholly 
impervious. The nerves of animal and of 
organic sensibility, intimately associated with 

> 8e» Apptndlx, Kota A^ 

the minute vessels of the skin and macoua mambrane, 
I have suflicienily described (290). 

337* 1 have been thus minute and particular in de- 
scribing the great limiting membrane which constiT 
tutes the confines of the vital domam, becJtuse it is 
the seat of many of the mo^it important functions of 
the organic economy, and, as I have saM (330), ia 
constructed with reference to all the relations which 
the vital domain holds to the external world i and 
hence, it is impossible for any one to have a clear and 
full understanding of the laws of constitution and re- 
lation under which man exists, without knowing the 
organisation and physiological endowniients of these 
important parti, 


338. The mucous membrane, then, we perceive, ]■ 
the grand seat of all the primary processes of alimen- 
tation, of the various functions of secretion and ex- 
cretion, of respiration, etc. ; and hence, it is so ar- 
ranged as to constitute the most important portion of 
all the organs by which these functions are performed. 
Having lined the mouth and nasal cavities, it passes 
back, and unites in the fauces or throat, and thence 
descending, forms a funnel -shape cavity called the 
pharynx, which tapers downward and gathers into a 
tube. This tube, called the esophagus or meatpipe, 
continues downward some twelve or fifteen inches, 
and having entered through a small opening of the 
midriff or diaphragm (fig. 37), into the abdominal 
cavity, it suddenly expands into a large sac, which is 
called th e s tomach . Th is sac has som e wh at th e shape 
of a pear (fig. 23)^ and lies across the upper part of 
theabdominalcavity. Itisordinarilycapableof con* 
taining from one to two quarts, but may he greatly 
enlarged by gluttony, and diminished by disease Its 
largest end lies on the left side, or in what is called 
the left hypochondrium. Ft diminishes in size as it 
proceeds towards the right aide, where it rather sud^ 
denly contracts into a tube, which is considerably 
larger than the meat pipe or ce^ophagus (fig. 23, f). 
This tube is prolonged to six or eight timai the length 

Fii. 23. 

a, the mtopliagiu or meatpipo; b, tlie eiidiac oiifict i t, I2i« py^ 
loric ormce ; d, th« siqaU vurrahire of th# itu^iCAcb ; «, thcr gt^ult 
^tumtitiv; f, tb« daodeBmn ; j. the cenliv af cb« stomttchi ^ 
th« t^lenie purUoa of the itomacl] (3MJ. 



of the body, and is nicely convolved or folded, so as to 
be brought within a small compass (fig. 24, «). In the 
descriptions of anatomy and physiology it is artificially 
divided into three parts, called the duodenum, the je^ 
junumy and the ilettm. It is more properly, as a whole, 
called the small intestine, or the small portion of the 
alimentary canal or tube. This tube, at its lower 
extremity, suddenly expands into what is called the 
colon, which is much more capacious than the small 
intestine (fig. 24, u). The colon ascends to the sto- 
mach on the right side, arches over the whole volume 
of the small intestine, and descends on the left side ; 
forming, in its lower part, what is called the sigmoid 
fiexure : or, assuming the shape of an S ; and then 
enters into the formation of a somewhat smaller tube, 
called the rectum (fig. 24, v), at the lower extremity 
of which the mucous membrane again blends with the 
outer skin. 

339. Such is the general disposition of the mucous 
membrane, in forming the alimentary cavity. 
Throughout its whole extent, some of its little vessels 
(331) exhale an aqueous vapor or serous fluid ; through- 
out its whole extent, its numerous little glandular fol- 
licles copiously secrete, and pour upon its surface, a 
lubricating and sheathing mucus, to keep its myriads 
of delicate little organs (287) in a proper state for the 

Fig. 24. 

a, fh« under side of the liyer ; 6. e, d, g, the bfliaiy ducU ; *, the gall- 
bladder; m, the eromach; p, the pylonia ; r, «, small iBtctiine, urmi- 
Bating at I in the large intMtine «, w, X, T. 

performance of their functions, and to protect thiem 
from the injurious action of whatever substances may 
be introduced into the cavity. 

340. In the oral cavity, on each side, near the second 
double tooth in the upper jaw, the mucous membrane 
forms a little tube (fig. 25, 6), which ascends along the 
cheek, and branches out and forms a gland in the man- 
ner I have described (334^, in front of the lower part 
of the ear (fig. 25, a). Another smaller one of these 
glands lies just within the lower edge of the under jaw, 
on each side (c) ; and a third and still smaller pair lie 
under the roots of the tonfi^ue, uniting on the middle 
line. The ducts of these mst two pairs open into the 
mouth in front of the roots of the tongue and near its 
bridle. These are all called the salivary glands. They 
secrete the saliva or the solvent fluid of the mouth, and 
pour it into the oral cavity freely during the process 
of mastication, and whenever any exciting substance 
is taken into the mouth. The smell, and sight, and 
even the thoughts of savor^r or disgusting substances, 
and of other objects of desire, will also cause an in- 
creased secretion and flow of saliva. The oral cavity, 
I have said (338), continues back into the funnel-sha- 
ped cavity, called the pharynx. Into this last cavity 
open also from above, the canals coming from the nose; 
and near them, on each side, a little tube 
coming from the internal chambers of the 
ear, called the Eustacian tubes. These 
tubes are lined by the mucous membrane, 
and are so essential to hearing, that if 
they become closed up, deafness is caused. 
Just in front of these is the soft pendulous 
body commonly called the palate ; but in 
the descriptions of anatomy, the vail of 
the palate. This, in the act of swallow, 
ing, is pressed back, and closes the nasal 
canals and the Eustacian tubes, so that 
nothing can pass into them. A little 
lower down, near the roots of the tongue, 
in the front part of the pharynx, opens 
the larynxy or the mouth of the windpipe. 
This is so situated that ever^ thing which 
is so swallowed must pass directly over it. 
To prevent any of the food or drink from 
entering the windpipe, a small oval-shaped 
cartila^nous valve is placed over the ori- 
fice. JSut as respiration requires that the 
mouth of the windpipe should only be 
momentarily closed, this little valve called 
the epiglottis is always raised, except dur- 
ing the act of swallowing, when it shuts 
down over the orifice, and completely 
closes it for an instant, while the food or 
other substances are passing, and then 
immediately opens.* 

341. Descending again to the stomach, 
we find that the cesaphagus or meatpipe 
does not enter this cavity at its end, or in 
the line of its longitudinal axis, but, as it 
were, at its upper side (fig. 26, a), so 
that the inferior mouth (c) of the stom- 
ach, which opens into the small intestine 
Qf), is little lower than that at which 
the food enters (a), and which on account 
of its proximity to the heart is called the 
cardiac orifice. The inferior mouth of 
the stomach (c), which lies in the right 
side of the abdominal cavity, is called the 
pyloric orifice. About four inches below 
this orifice, in the small intestine {d), is 
the mouth of another tube, formed or 
lined by the mucous membrane. 

• The fket that the glottis can close itself in the 
absence of the epi-glottis does not in the least de- 
gree prove that the epi-glottis is not designed to act 
exclusively as a valve to close the glottis in the act 



Tbii tube &ic«nd» and branch^ out m tlie manner 
I have deacribed (334) ; and, together with appro- 
priate vesielsj nerves, etc.j forms the largest gland in 

Pig. 25. 

a, the uU^ary gland in the ch^fik ; b, the duet Uniting to *he 
mouth , ct tke gUnd uutler thi f^dge ciF the under J4W. 

the body, called the lirer (fig. 24, a a a). This 
gland h situated at the top of the abdominal cavity, 
and lies immediately under the diaphragm, and most- 
ly on the right side. It is divided into a large lobe, 
uid two Email ones. On the lower anrface of the large 
lobe, which Ue* on the right side, is formed a mem- 
branouB reservoir, called the gall*bladder, which is 
aho lined by^ the mticous membrane (fig* 24, 6). The 
cammon biliary duct, after proceeding a short distance 
from the small intestine, givejt off a tube called the 
ciatic duct» which goe^ to the ^11-bladder. The re- 
maining portion of the main duct, which now takes 
Ibe name of the hepatic duct, continue* a little 
ther, and then divides into two tubes, one of which 
goes to the right and the other to the left lobe of the 
Hver, The nerves of the liver, which are vtry nu- 
meroui, are principaDy from the hepatic plexus, which 

Fl£. M, 

a, the cftrdiat^ orifice of the Btomach ; b^ the littertor of the «toro- 
ich *t c, the |ij^lorus; 4, the iDterlar of thu duodenucp. 

is formed by a multitude of the branch^ of the nerven 
of organic lifv, and into which some of the filamenta 
of the pneumogastric penetrate (245, 2S5). By this 
plexus, also, the liver is brought into very immediate 
and powerful anatomical and aympathecic relations 
with the stomach (231), 

542* The pancreas, which very closely resemble 
the salivary glands in its structure and in the charai^. 
ter of its secretion (fig. S?)? is situated behind the 
stomach, and lies crosswise of the body (tig. 2B, p p). 
It is about six inches long and one thick, and weighs 
from four to six ounces. Its dnct generally enters 
the stnaU intestine, at the satne point, and in a eom. 
mon mouth with the biHary duct. These excretory 
ducts, and those ot other f^lands, though formed essea* 
tially of the mucous membrane, as I have said, have 
also an exterior tunic of denize cellular substance. 

343. These are the glands which immediately per- 
tain to the mucous membrane of the alimentary cav- 
ity, and are more or less concerned in the performance 
of its general function of assimilation. 

344. The kidneys, which are situated in the re- 
gion of the loins (fig. 28, A-), though they, like the 
glands just described, are founded upon the mticoua 
membrane, are not immediately connected with the 
alimentary canal. The mucous membrane, which 
lines all their ducts and cavities, continues Irom each 
kidney, and forms or lines a long tube about the size 
of a writing quill, one of which descends from the 
kidney on each side, and opens into the bladder (tig. 
28, u ti). From these tubes the mucous membrane 
continues and lines the bladder, and thence proceeds 
to join the external skin. 

346, The tachrymal glands (tig. 49, a) which secrete* 
the fluid that moistens the eyeball and composes the 
tears, and the other glands of the body, not p&rticn. 
larly described, are all constructed upon the same 
general principles, having the mucous membrane for 
the grand foundation of their structure. But in all 
these glands this membrane is, as it were, isolated, 
and at a greater or less remove from the great sheets 
o^f the alimentary and respiratory cavici^* Yet when 
It is remembered that the main diBerence between the 
external skin and the mucous membrane (2R7> 289) 
is in Hiuaiifjn^ which affects function more than stmc 
ture, we see that the one may readily pass into the 
Other, in any part, according to thegeneiid and poLrti- 
culor wants of the organic economy. 

MB, Passing downward from the month of the 
biliary and pancrL'Fi tic ducts (34 U 3-12) along the imall 
mtentine, we find the orfpan abounding in flmuU semi- 
lunar folds (fi^. 29) called the vahuits conniventts^ 
which greatly i n create the e stent of its surface, and^ 
cause its contents to descend more nlowly. Tbi* in- 
testine does not pans into the large portion of the canal, 
in the line of its longitudinal nxis^ as a eon tin nous 
tube, but enters in at a rt^bc angle (tig. 30, h) about 
four inches above its juferinr extremity (a), and 
terminates in a circular fold of tbe mucons mem- 
brane, called the iko-^osf^al valvst whiish extends, 
by its free border, into the cavity of the large in- 
tesitine, and suffers the contents of the small intes- 
tine to pass freely into tbe large, but diies not per- 
mit those of the large intestine to pass into the 
small. The portion of the large intestine which 
extends below the ifeo-cflecal valve (tig. 30, a), is 
caHed the ccecum. It has the form of a sac open- 
ing into the colon (tig. 30, 6 € d)y and is three or 
four inches in depth, and about the same in dia- 
meter. The colon is not cylindrical like tbe small 
intestine, but is gathered into partial circular folds, 
which give it a saculated form and appearance, 
and is secured in this condition, by three longitud- 
inal bands (fig. 30). In the rectum (fig. 30, /), 
this saculated form disappears, and the canal 
again becomes more uniform and cylindrical. 



F^. sr. 

The Faacrcu. 

Fig, 2B. 

thfi Mrta; b, tha bladder; ff^ the jsraU-Uadder: *, the WdneTi; I, tie 
liT« turned upj showUiff tha under iidfl? p, the paiie«»; r^ Uie reetttifi ; 
4, th« spleen; u, the uretufeA; p, tha vena c*va. 

Fig. 39. 

Section of the <mall Inttititte turned infiide ^at, to thaw tha foldi of i^ 
raucoui mvmljrtuep 


34?. Motion, as well asinnerraticm and 
secretion r being tieceuary for tbe perfor- 
mance of the ^neral functions of the 
aUmentary cavity^ muscular fibres are 
therefore everywhere attached to the 
back of the mucoui membrane formiDg 
that cavity. These fibres are arranged 
in different parts according to tbe mo- 
tion required. Throughout the whole 
extent of the canal, however, tie ar- 
rangement ia very similar (199). In 
general, it consists of two layers; the 
first composed of circular fibrea^ which 
surround the meatpipei the stomach., 
and the small and large intestinesj like 
rings, or like sections of rings, whose 
ends lap by each other, so as to git e the 
muielea more power and activity ; and 
the second composed of longitudinal 
fibres, or those which run length wise of 
the meatpipe, stomach, and iiitestinal 
tube (338). By the contractioa of the 
circular fibres, t^e calibre of the cavity 
is diminished. By the contraction of 
the longitudinal fibres, the parts are 
shortened, and by their raimbined action^ 
they give the parts a vermicular or undu- 
lating motion. The tntiacular coat thus 
formed is considerably thicker and more 
powerful in the meatpipe and stomachy 
than in the small intestine ; and in the 
large intestine, particularly the colon j it 
is still thinner than in the small. In the 
cnlon^ also, the longitudinal fibres^ in^ 
stead of forming a continuous layer or 
sheet, as in the other parts, are gathered 
(346) into three separate Jongitudinal 
bands {^g. 30), In the rectum, again^ 
the muscular coat becomes thicker and 
s^tr€^ngerj, and the longitudinal fibres form 
a continaons layer around the tube. In 
the pharynx (338) the arrangement Is 
somewhat different: here the musculair 
coat is composed of six constrictor rous* 
c3e», the fibres of which form sheets 
which cross each other in various direc, 
tions. By the action of these muscle* 
botk the length and calibre of the 
pharynx are diminished. In the sto^ 
mach ih6 fibres are disposed in three dif- 
ferent dirftctions : longitudinally, circu, 
larlyj and obJiquelv, At the pyloric 
orifice of the atomacn, the circular fibres 
gather into a thick and powerful baud 
or riagp which j together with a thicken* 
ing or folding of the mucous membrane 
upon itself^ forms what is called the val^S 
ofths pyl&Tus (fig* 26, (r), or mora com- 
monly the pylorus or 'gate keeper/ from 
which the ori fice derives its name. 
When this ring is contracted, the orific* 
is closed J so that nothing can escape 
from the stomach downwards* Its office 
is to prevent the contents of the sto- 
mach rrom passing into the small intes- 
tine in a crude and undigested state. 

34d> It is an interesting physiological 
fact, that the muscular coat of the ali- 
mentary orgtns, and particnJarly of the 
stomach and small intestines^ is more or 
less developed and powerful and active, 
according to the character and condition 
of the food on which the iDdividual 
habitually subsists. Those kinds and 
i conditions of food which require con- 



siderable muscular action and power in tbe alimentary orgam, 
eondnc^e to the develop meut, vigor, and activity of the ^bres 
which form their muscular coat ; while the opposjie kinds and 
conditions of food couduce to the emaeiation and feebleness and 
inactivity of those fibres, and in Rome instance* the atrophy or 
wasting of tbe muscular coat of the i^tomach proceed! ta such a 
degree as to render its action exceedingly sluggish and feeble. 

9 bed?, nie eoloiii Adwih^ Ita laeulated form and geaeifjtl atrmnfetaeot :; e^ 
the iJgmoid flpxtnre ; /, th& rwruin ; A, the »siaU iBtHtina tcnnJiDq,U&g In 
tbe colom iind f&mujig the i]co-ctfic&l Talve ; g^ tliB tus«1j cnHSing th& 

349. Such 19 the general contractile tendency of the muKJuIar 
coat of the alimentary canal, thiit when itt sever elI partB are Dot 
distended with foodj their cavities are very considerably dimimih- 
ed ; and by this meani, the mucous membrane is gathered into nn- 
xnerous wrinkles or folds. In the me at pi pe^ thene are nearly longi- 
tudinal. Fn the stomach the wrinkles run in every directi on, 
And the folds are ei^ceedingly numerous (fig. 31); btit in both 
of these organs they wholly disappear when the parts are com- 
pletely distended. In the 'amaU intestine the fold* (fig. 29) are 
even more numerous (ban in the stomachy and many of them 
ate alio more permanent (34 G). 

fig. II. 

The fulii la tb« x^beoiiJ membrane of Lhc stotnach. 

350, The alimentary canal, thus con^ 
itnictedj is everywhere surrounded or 
embraoed by the serous mem braiie 
which line* the thoracic and abdomi- 
nal cavities (176), and which constUates 
one of the coats of the canal. The esso- 
phagas is embraced by thai portioQ of 
the membrane of the thoracic cavity 
^^hich forms the middle partition of the 
chest, caDed the mediastinum (176), and 
lies immediately in front of the spinal 
column. The serous membrane which 
sarrounds the stomach and the intes. 
tinesj excepting the duodenumj is called 
their peritoneal coat. It serFei in a 
measure, as I hava said (176), to isolate 
the organs, to present a smooth and lu- 
bricated surface, which enables the con- 
' tiguous organ B and parts to move upon 
each other without injury, and, by its 
various atta^^hments to the walls of the 
abdominal cavity and other parts, to 
keep each organ and portion of the ali.^ 
mentary catia2 in its proper and relativiB 
poaitiort (tig. 3'J), The portion of the 
membmne ^^hich thus accures the lutes ^ 
tines, forms a gathered or folded curtain 
which extends from the back -bone (figs. 
5 and 32 J m) to the convolutioni and 
arches of ihe canal ; and thus, while it 
holds every part in its relative position, 
admits of a free boating raotton of the 
whole. The curtain which beloogs to 
the small intestine is called the mejen- 
tery (fig, 33, c), and that which belongs 
to the colon, ihe mesocolon* Om these 
curtains also are ramified and distribu- 
ted in great abundance, the vessels and 
nerves that go to and from the aliment, 
ary canal (fig* 30, g). From the stom- 
ach, the arch of the colouj and the liver^ 
the peritoneum depends In e:£tensivo 
folds, the two laminie or sheets of whick 
are connected together by cellular tissue 
containing fat These folds are called 
the omenta, or la popular languai^e, the 
caul. The great omentum, which is at- 
tached to the stomach and arch of the 
colon, lies like an apron, free and fioat- 
ing upon the front of the convolutions of 
the small intestines (fig. 34, gg). The 
omenta are constantly moisteiied with a 
serous fluid whrch facilitates the more^ 
meuta of contiguous organs upon each 
other ; they also receive the superfluous 
depoaitions of fot. The three coata of 
the canal J consisting of the mucOTiS 
membrane^ the rauacular coat, and the 
pert ton eal coat, or the serous membrane, 
are clo&ely knit together by a delicate 
cellular tissue- The nerves distributed 
to the alimentary canal, and which pre- 
side over its function s, we hare ne^n. 
(220), are from the ganglionic System of 
organic life. These are exceedingty 
abuutiitiit in every part of the canal, 
imparting the stimulus of involuntary 
motion to its muscular ti&sue (219), giv- 
ing the functiotia! power of absorption, 
secretion, ejccretioiij exhalation, etc-j to 
its mjrriada of minute reasela (230); and 
organic sensibility, common and special 
(2y(j), to Its whole extent of mucous 
membrane (21H>), The stomach, we 
have seen (231), ts very largely sup- 
plied, not only from the great centre 
of organic lifcj but also from the centre 



of animal life {ti^)^ ^nd is thereby broaght into 
the most Imjnediate, powerful, and important rela- 
tions and sympathies witt each and eTery part 

F\s^ 12. 

Tlift dieted Bncshowi the urAiagenieiitDf th? mtovt mvwbTMnt 
In Che abdomLaal cav^Uy {U&]; llnmgpt tb£F hont waU of the iibdD' 
m«i, partUllj lurroundinjj 6 u r, the organi of the pelvis, and 
kf the kidney; going dowti around j, the intentine, and rflturotDg 
AadfojfflLiQg m, the me^ntQi^t ascending to d^ the arch of the 
fli&piu;)igza ; aad f urraiziiding i, the Jivci-j etc, 

of the system (297, 29S), The alimentary canal, 
howerer, being a general organ of «rtemal ae 
well as interual relatioiLi designed to receive foreign 
substances for the nourishment of the bc^dy^ and to 

Fig, 93- 

i h, Uie Iste^tuic ; e, the mesentflrj'. 

^pel the unappropriated portions, its superior and 
inferior extremities are accordingly farniahed with 
serves and must-lea which bring them under the cogni-* 

zance and control of the animal centre of perception 
and of Toiuntary action (233, 302). The mucous 
membrane of the mouth, nostrils^ throat, pharynx, 
and larynx or top of the windpipe, is highly endowed 
with animal sensibility of t<mch or feeling (294) ; that 
of the mouth J and particivlarly of the tongue, has also 
the sense of taste, and that of the nose the sense of 
smell. The control of the wrj,j,, or the voluntary 
antion, is nearly tomuiensiirate, in these parts, with 
the sense of feeling, and is exernLHed in chewing, swal- 
lowing, speaking, singing, etc. The nerres from which 
these parts derive their animal sensibilities and power 
of voluntary action, I have fuUy described (245J^56). 

a b c, the itomoch ; g g, the great omeu turn or cauL I 

RE^pinATony ajtd vocal oeoaks, ' 

331. The respiratory organs are closely associated 
with the alimentary. Indeed they constitute a part 
of the great assimilating apparatus of the system, for 
in them is completed the process of assimilation, which , 
commences in the mouth or stomach ; and, like the ali- 
mentary canal, the lungs are organs of external as well 
as internal relation, and consist fundamentally of the 
mucons membrane. 

352. In the function of respiration or breathingH,. the 
trachea or windpipe, lungs j diaphragm, ribs, and 
breast-bone, with numerous pairs of muscle which 
move these bones, are the principal organs employed. 

353. I have said (340) that the wiudpipe opens into 
the pharynx on the front sidcj just below the roots 
of the tongue. Here the tnucuous membrane conti- 
nues down from the pharynx^ and forms a tube about 
the size of the meatptpe when that organ is fiilly dis- 
tended, or lesa than an inch in diameter. This 
tube descends several inches in front of the meat- 
pipe to the cavity of the chest, where it divides into 
two branches, the one going to the right, and the 
other to the left side of the thoracic cavity. Here, 
each of the branches divides and subdividesi in every 
direction, like an artery of a gland (fig. 21 )j ttU they 
form a thick brujh or broom of minute hollow twigs^ 
and each of these twigs terminates in a little celL 
These little air cells are supposed to be about the one- 
thousandth part of an inch in diameter, and their 
number in both hmgs is estimated at more than one 
hundred millions^ Sy this arrangement the mucous 
membrane of the lunj^ presents an extent of surface 
to the air which is said to be equal to that of the whoie 
external skin, and some anatomists say that it is much 
greater. It has been estimated at twenty-one thou* 
sand square inches. But estimates of i^his kind can- 
not be very exact. As the air enters the windpip^ 
and lungs principally by suction, as we shall see, these 



tubee would all colJ&pAe or cloie up, If they were, like 
the m^Aipipe^ P^^^h membruioiis. To keep th^sm 
diHtended, therefore, and to enable the iadividu«l by 
the voluntary conlrol of the respiratory apparatui to 
produce mjmd or v^oica in the emiision of the air front 
the hmg&j various cartilages and muadet are supplied. 
The part* more particularly oonstructed and armnged 
for the production of voice are placed at the top of the 
windpipe J and collectively called the larynx j which is 
attained above to the bone of the ton^e, and behind 
ii coainected with the CBsaphagiiB or meat pipe. It is 
impossible to describe these parts in such a maxuier 
as to gi re a clear and acctiiate idea of them to those 
who have never teen them, without extensive visible 
illustration B, and as their minute anatomy will not 
serve to elucidate any Important pbyf^iological princi- 
ple-j 1 shall only give a general description of them. 

554. The larynx ia composed of five cartiJages, 
which are moveable one upon another bv the ac- 
tjon of sevexal muscles, 1 , The th^roidj or shield-like 
cartilage {^gs^ 3S, 36, a), which is the largest of th« 

Fi£. »s. 

(340). * On the Inside of the larynx there are two liga- 
tnenia, formed of elastic and parallel iibreij and extend- 
ing forward from the anterior part of each arytenoid 
cartilage to the thyroid cartilage, where they meet* 
These are called the chordm vocales, or the vocal liga- 
ments (fig, 3ti,/). The opening between then is uie 

Fig. m 

five, and forms the upper and anterior part, and pro- 
duce at the upper part of the neck the prominence 
called ^dtwm'j aipfe, 2. The mcdrf or ring-like car- 
tikge (6), which is placed below the thyroid, and like 
that can readily be felt in the fore part of the neck. 
It is narrow in front, and thick, broad, and strong 
behind. Its upper edge has its front part fixed to the 
thyroid cartilage j its lower edge is connected to the 
whole circumference of the commencement of the tra- 
chea. 3. and 4. The two aryienoid, or small pyramid- 
shaped cartilages (fig. 36, c), which are situated at the 
upper and back part of the larynx, above the cricoid 
cartilage, to which they are attached by a strong liga- 
ment (iig- 36j e), and upon which they have a sliding' 
motion in every direction. 5* The ^'pi^toith^ a softj 
fibro-cartilage of an ovoid form, situated at the upper 
part of the larynx under the roots of the tongue, and 
placed obliquely over the glottis or mouth of the wind- 
pipe, which opens into the pharynx, forming a ^^y^ 
by which the glottis is dosed in the act of deglutition 

entrance into the windpipe, and is called the glottis. 
This narow chink is capable of being enlarged, con- 
tractedj or wholly closed. Immediately above these 
two ligaments are two stnaH pouches, termed the ven- 
tricles of the larynx ; and above the ventricles are 
situated two other ligaments formed of a mucous mem- 
brane, and extending between the arytenoid and thy- 
roid cartilages, above the chorda vocuies ; so that the 
ventricles of the larynx are situated between these 
ligaments and the vocal chords. 

366. ^ All the modifications of the voice are produ- 
ced by the air passing out of the lungs through the 
larynx. The sound is occasioned by the vibration of 
the vo(^ ligaments. According to Magendie, the 
gravity or acutetiess of the sound depends on the 

K eater or less approximation of the arytenoid earti- 
ges towards each other. But Slayo remarks that 
the pitch of the voice has no reference to the siie of 
the' aperture between the vocal chords j nor to any al- 
teration of their length, but depends solely on their 
tensi&n^ and, consequentlyj on the frequency of their 

366. The whole larynx may be elevated towards 
the chinj or depressed towards the sternum j by the 
action of appropriate mUBclea situated in the parts. 
It is supplied by four nerves, all of which are fur« 
nished by the pnenmogastric^ which I have described 

357« From the larynx downward into the lungs^ the 
windpipe is kept in a distended form, by a succession 
of fibro-cartilaginous rings connected with ^ch other 
by a membranous texture (fig* 3d, c, 36y d)-, For im- 
portant purposes, however, these ringn^ as they are 

• Oliver'a Fim Llnei of Phyiiolofy j p. 453. 

t In tsontf »nd s&nivwhat below die Iatjilx, Is iltuated s icrft, 
ipcmgyljody called the thyioidfliitid, the ueeof whieh i« not kisowii. 
Iteonsiju of two lobee, one on tath aidci whkh are united in the 
middle {flg. S&, d). ft receiTefl blood from four atteTieH, but hu nb 
excretorj duet. It 14 utuaJly Urger in fisTQ&lefi than la maJi«, sad 
liLTgei ia e^rly life tban in more ftdvaQi^ed a^e. 



called, are not entire cirdei» but each ring describes 
sbcut two-thirds of a circle, and the other third is oc- 
cupied by a membranous texture of muscular fibres 
running in the direction of the rings : so that their 
contraction draws Hxb two encte of the rinff nearer to 
each other, and thus considerably diminishes the cal- 
ibre of the windpipe. This mufculo-membranous por- 
tion is in the back part of the windpipe, and contigu- 
ously in front of the ossophagus or meatpipe : so that, 
when a bolus of food descends in the cesophagus, its 
course is not obstructed by the cartilaginous rings of 
the windpipe, as would be the case if they continued 
entirely around. But if tiie bolus it too lar^e, it 
presses in the membranous portion of the windpipe to 
such an extent as to cause the distressing sensation of 
choking^ and in some casea so nearly doses the wind- 
pipe as to cause suffocation and deam. 

358. As the branches of the windpipe become more 
and more subdivided in the substance of the lungs, 
the rings become less and less cartilaginous, and gradu- 
ally soften down and £sde away, and finally disappear 
entirely, leaving nothing but tne membranous form of 
the small air-tubes. It is however asserted by some 
anatomists, that the transverse muscular fibres,' by the 
contraction of whidi the calibre of these tubes is di- 
minished, are continued down to the smallest subdivi- 
sions, and that they are employed in the act of expi. 
ration, in expelling the air from the lungs ; and that 
it is to this contractile tissue that the pulmonary 
branches of the pneumogastric nerve are mainly dis- 
tributed (245). 

369. A large pulmonarv artery,, rising from the 
heart (fig. 40^ k), divides like the windpipe (353) into 
two branches, one of which goes to the right branch 
of the windpipe, and the other to the left. These now 
ramify in the same manner as the windpipe (fig. 21), 
so that their branches and twig^ correspond with those 
of the windpipe ; and finally, the extremely minute 
twigs of the artery terminate in the sides of the air- 
cells at the extremities of the minute air-tubes (353). 
Where the arterial capillaries terminate, the venous 
capillaries rise, and, running into each other, the 
vessels become larger, and form branches correspond- 
ing with those of the artery, till they swell into lar^e 
piumonary veins, which emerge from the lungs by the 
aide of the arteries and proceed to the heart (fig. 40, 

3G0. These pulmonary arteries convey the blood 
from the heart to the lungs, where it undergoes im- 
portant changes, and then the veins carry it back 
mim the lungs to the heart. The lungs, however, 
are not in the least degree nourished by this circula- 
tion. The bronchial arteries, which nourish all the 
tissues of the lungs, and the veins which correspond 
with these arteries, are ramified like those just des- 
cribed, and extend to every portion of the piUmonary 
structure. Besides these, lymphatic vessels are nu- 
merously distributed in every part. All these vessels, 
and especially the arterial capillaries, are lai^ly sup- 
plied with nerves of organic life, which preside over 
their functions (230). Some of the branches of the 
pneumogastric nerve (245), after interlacing and form- 
tng plexuses with nerves of organic life, proceed to 
the lungs. These are supposed by some physiologists 
to be wholly appropriated to that peculiar sensibility of 
the lungs by which we feel the want of air ; others 
think they are exclusively distributed to the contrac- 
tile tissue or muscles of the air-tubes, just described 
^68), and convey to them the stimulus of motion. 
Others, perhaps more correctly, suppose that they 
perform both of these offices. AU these air-tubes, ves- 
sels, and nerves, are closely knit together into one 
general texture by a delicate cellular tissue (171)) and 
the whole mass, on each side, is enveloped in the se- 
rous membrane as an external coat (176). 

361. The right lung is larger than the left, and is 
divided into three lobes (fig. 37, a a a). The left has 

two lobes {b b), and is smaller than the right lung, 
to make room for the heart (171)9 which lies partly on 
the left side (fig. 4, h). The lungs of men are in gen- 
eral larger than those of women. Each lobe of the 
lungs is divided, in its internal arrangement, into nu- 
merous lobules. The air-cells (353) of each lobule 
communicate with each other, but the cells of one lobule 
have no direct communication with those of another. 
The two lungs are completely separated from each 
other, and from all the other organs, by the serous 
membrane, here called the pleura (176), which lines 
the thoracic cavity, and divides it into two chambers, 
by passing double across it from the breast-bone to 
the back-bone (fig. 37, c), and thus forming a closed 
sac for each lung, and embracing the heart, the large 
blood-vessels, and the meatpipe (350), between the 
two sheets of the mediastinum or middle partition. ^ 

362. By this arran^ment, every part is kept in its 
proper place and condition, and an admirable provision 
IS made against evils which might otherwise arise from 
injuries of the chest and lungs. If instead of being 
completely separated as they are, the two lungs occu- 
pied one cavity, then any perforation of the walls of 
that cavity, by disease or otherwise, so that the exter- 
na air could rush into it, would at once arrest the 
function of respiration, and immediate death would 
result. But now, if by any means one lung is disa- 
bled, it can lie still while the other continues faith- 
fully to perform its function ; and thus life is preser- 

363. The diaphragm (175) is a musculo-tendonous 
membrane, which is attached by its two legs to the 
two upper vertebra of the loins (fig. 38, a), and pro- 
ceeds diagonallv upwards and forwards, arching up 
into the cnest like a bridge or dome (fig. 4, and 32, 
d), and, being attached by its peripheral edge to the 
walls of the body, all around (fig. 38, 6 5), so as com- 
pletely to divide the trunk into the two large cavities 
(I75) called the thoracic and abdominal (fig. 38, c a). 
The meatpipe, the large blood-vessels, etc., pass 
through this partition near the spinal column. The 
legs and centre of the diaphragm are principally ten- 
donous, and its wings are muscular. By the contrac- 
tion of the muscular portions, the arch of the diaphra^ 
is reduced nearly to a plane, and thereby the cavity 
of the chest is enlarged and that of the abdomen some- 
what diminished, the liver, stomach, etc., being pres- 
sed down by the descending diaphragm (fig. 4). 

364. In describing the bones of thie body, I said 
(181) that the ribs (fig. 8, ceo) are fastened by car- 
tilages and ligaments to die spinal column {b 6), and 
most of them by a double attachment, and that thev 
droop as they proceed forward to be connected with 
the sternum or breast-bone («) ; so that the front ends 
of the ribs, when in their most natural or resting po- 
sition, are considerably lower than the back ends 
(fig. 8). By this arrangement, when the various mus- 
cles concerned in elevating the breast-bone and the ribs 
are contracted, the breast-bone and the front ends 
of the ribs are raised up so as to brine the ribs nearly 
to a horizontal position; and this also considerably 
enlar^ the cavity of the chest. When, therefore, 
the diaphragm is drawn down, and the breast-bone 
and ribs are elevated, the cavity of the chest is much 

366. It is a matter of general knowledge, that the 
atmosphere has weight, or that like other ponderable 
substances, it gravitates towards the centre of the 
earth ; and diat it presses on the surface of the earth 
and things on the earth, at or near the water^s level, 
at the rate of about fifteen pounds to every square 
inch of surface. This pressure being the same on 
every part of our bodies, we do not feel it. But if 
the air could be entirely expelled from the lunp, and 
the mouth and nose completely closed, and the thoracic 
cavity enlarged, as in a fuU inspiration of breath, there 
would be a pressure of many hundred pounds upon 



a aj Cbe r^ht liiqg; t i, the left lung; e, the niedtasdnmn i 
the lap of Che wludFlpe. 

1 the esttemal fiur&ce of the clieat. But the n4»e being 
opeuj the air rushes into the wind pip e^ air-pussAgea, 
and cells of the hings, and distends these orguns, so 
that they at all tinier just fill th^i CAvitita allutted to 
them J and no vacuutn is produced^ and tousequently 
no pressure is fek* In ordinary breath lugj thereforej 
the musclefl whieh elevate the breast-bone and ribsj 
jlij^htly contract J a^d the arch of the diaphragm (6g. 
32, d) is simultaneously drawn down^ and thereby the 
cavity of the chest is enlarged, and at the same time 
the air rtjshes in and inliates the lungs ; and then all 
the muficles employed in producing these motions in- 
stantaneously relax, and the rftis and diaphragm re- 
turn to their natural position ^ by the elasticity of the 
cellular tissue {l(il>), the force of gravity, and the 
pressure of other parts* Bv these means, and perhaps 
also by the contraction of t^e muscles of the air-tube* 
{:it>y), the air is expeUed from the lungs, 

35B. When the ribs are confined by tight clothing, 
the diaphragm is compelled to carry on the function 
alone, but In this case respiration is much restrained. 
In violent and rapid brea thing j the abdominal mus- 
cles probably assist in the act of expiration* We see 
then that it is not by a direct action of the WILL upon 
the lung?4, but upon the diaphragm and the muscles 
which elevate the breast-bone and ribs, and upon the 
parts which compose the larynx or orgaiis of voice, 
that we have^ to some extent^ a voluntary control over 
the acts of inspiration and expiration t and this we 
have seen {34i^), ia necessary in order to the protection 
of the lungs from oiTensive air, etc,^ and to the pro- 
duction of^voice, speechj etc»; but when neither of these 
final causes demands the immediate exercise of the 

d tt 

FJg. 5$. 

Tho dijipbTJiiimi during erpfmtjoa ; ti. Its taadQDQUt 
centre; b b, its ties Ny eiders c c, the Uteiral QxfiU^ 
otthv che^t in which the lun^a lie. 

wiLt.j the function of respiration is wholly 
given up to organic instinct, and is carried 
on without our care, aud in health gene- 
r&Uy without our consciousness. All the 

muscles of an i maJ life, theref orcj cone erned in 

the general functions of respiration, arc associated in 
the regular performance of this function, with thoie of 
organic life or of involuntary motion, 


367. The general func tion of ci rcula tlon i n in t imate- 
ly associated with that of respiration. The organs 
employed in the performance of this function are the 
heart, arteries, voinsj, and capillary vessels (313). 

368, The heart is a muscular organ (172) having 
somewhat the shape of an inverted cone, and lying, 
as I have said (361 )j in the lower part of the thoracic 
cavity, between the two sheets of the pleura, which 
form the central partition of the chest (fig* 37, c)* It 
is also surrounded by a membranous sac of its own 
(176), called the pericardium (fig* 3% 6 &), which j by 
its exhalations, con timially moistens and lubricates its 
enclosed organ. The heart lies partly on the middle 
line, and partly in the left sideof thec'best (fig. 3D, a)* 
Strictly epeaking, it la a double organ, composed of two 
corresponding halves, each half having an upper and 
a lower chamber or cavity- The npper chambers are 
caDed auricles, and the lower ones ventricles (fig, 40, 
a b n). 

3(^, Before birth, there is an opening between the 
auricles, through which a portion of the blood paiSSE^ 
from the right auricle to the left ; but after respiration 
commences, there is no direct communication between 
the two halves of the heart. The auricle on each side^ 
however, communicates freely with its corresponding 
ventricle. The cavities of the right aide of the heart 
are somewhat more in front than those of the left, 
Tbe right auricle receives the dark blood that returns 



Fig. 39. 

The cavity of the chest laid open, to show the heart and lungs. — 
a, the heart ; d 6, the pericardiam, cut open ; e, the aorta, the 
great artery of the left side, that distributes the blood to all parts 
of the body ; d, the great vein, called the descending vena cava, 
which, with the ascending, brings the blood to the right auricle; 
e, the pleura or membrane that covers the lungs. 

in the veins from all parts of the body, and, contract- 
ing npon it, sends it into the right ventricles through 
an onfice which is furnished with membranous folds, 
80 arranged as to form a triplex valve, called the iri- 
cuspid valve; which, being pressed back, closes the 
orifice, and prevents the blood from returning to the 
auricle. The pulmonary artery, which I have already 
described (359), rises from the right ventricle (fig. 40, 
k), and soon divides into two branches, called the right 
and left pulmonary arteries, which are ramified (fig. 
40,11) with the branches of the windpipe, in the for- 
mation of the lungs. The orifice of the pulmonary 
artery is furnished, internally, with three membranous 
folds, called the semilunar valves. These suffer the 
blood to pass freely from the heart into the arterr, but 
prevent its returning from the arterv to the heart. 
Through this artery the right ventricle sends its dark 
blood to the lungs, where it is changed into bright red 
arterial blood, which is conveyed to the left side of 
the heart by the pulmonary veins which I have also 
described (359). These veins, advancing from the lungs 
in two trunks on each side, open into the left auri<?e 
(fig. 40, f» m). From this auricle the blood passes into 
the left ventricle, through an orifice like that on the 
right side, which is furnished with a fold of membrane 
tilled the mitral valve, which prevents the blood from 
returning to the auricle. From the left ventricle opens 
the mouUi of the great arterial trunk called the aorta, 
through which passes all the blood that nourishes the 
l>ody. This orifice is furnished with three semi-lunar 
halves similar to those at the entrance of tilie pulmo- 
nary artery, and which like them suffer the blood to 
piiM from the venticle into the artery, but prevent its 
returning from the artery to the ventricle. 

370. It is probable that, at first, the 
heart consists only of the left ventricle 
(219), and that the other parts are ad- 
ded as the general development of the 
system progresses. It is not, however, 
until respiration, and with it the pulmo- 
nary circulation, commences, that all the 
cavities of the heart come into the regu- 
lar performance of their appropriate 

371. The muscular power required in 
the auricles being much less than in the 
ventricles, the walls of the former are 
much thinner than those of the latter. 
The right auricle is somewhat larger 
than the left. The cavities of the ven- 
tricles are nearly of a size, but the walls 
of the left are much thicker and more 
powerful than those of the right. 

372. In the actions of the heart, the 
two auricles contract simultaneously, and 
the two ventricles contract simultaneous- 
ly ; but the auricles and ventricles con- 
tract alternately ; so that as the two au- 
ricles contract, the two ventricles dilate, 
and as the two ventricles contract, the 
two auricles dilate. 

373. The muscles of the heart are sup- 
posed by some physiologists to possess a 
peculiar irritability (231), which causes 
them to contract from the stimulus of 
the blood in the cavities, but it is more 
probable that the heart has cognizance of 
the blood in its cavities, by means of its 
nerves of organic sensibility (230). Some 
also suppose that a positive distending 
muscular force is employed in the dilata- 
tion of the cavities. But this appears to 
be both impracticable and unnecessary. 
The elasticity of the cellular tissue is pro- 
bably sufficient for that effect (158, 312). 

The nerves of organic life, I have 
« . said (219), preside over all the func- 
tions of the sanguiferous system. The heart, 
which in its rudimental state is closely con. 
nected with the central brain of that system (219, 
231), is gradually removed as the several parts 
are developed, till it becomes established in the tho- 
racic cavity ; and the ganglionic masses, from which 
its nerves principally issue, are situated in the neck 
and upper part of the chest. Some of the branches of 
the pneumogastric, it will be recollected (247)> enter 
also into the cardiac plexuses, but few if any of them 
reach the heart. At any rate, they neither bring it in 
any degree under the control of the will, nor render 
it cognizable to the centre of animal perception (302). 
The heart, therefore, is entirely independent of the 
WILL, yet its action is more or less accelerated or re- 
tarded by every emotion of the mind. This, however, 
principaDy depends on its organic sympathy with the 
stomach, and with the great centre of organic life, and 
through them with the brain (303). For the heart is 
in no degree the seat of those emotions or feelings 
which are, in common language, referred to it. 

374. From the left ventricle of the heart, as we have 
seen (369), rises the great arterial trunk, called the 
aorta, or air-keeper (so named by the ancients, because 
they supposed all the arteries were air-tubes, they being 
generaUv found empty after death). This trunk as- 
cends a short distance towards the head, and then forms 
an arch (fig. 40, c ef), and descends behind the heart, 
and in front of the spinal column, passing through the 
diaphragm, and dividing in the lower part of the ab- 
dominal cavity, to proceed to the two lower limbs (fi^. 
28, a). Almost immediately after leaving the heart, it 
gives off two branches which go to nourish that organ; 
tor neither the heart nor any of the blood-vessels re- 



ceiTein<>uriB!iment directly from the blood which flowi 
in h ; hut tijey are all, even to the smaUest vesaelflj 
Hoiixiilied by arteriea distributed to their tisfitie* for 
the Bpeoml purpose. At the top of ita arch, the aoria 
giyeft aff thr^e mtge branches (ng< 40^^^ i)^ which ar« 

F%. 40. 

a, the leftFfiitrlde: S, the i-ight ventricle; c f /, the aorta, thir 
g»&t artiify thit goes off from th« kft veiitrJcle ; j A ^, Oie arteiiei 
tliiit are tent from the arch uf the aorta ; *, the pulmDDAry utery* 
ihatgoci frtJBi thi right veotricl*^ to.the lungs 5 tl, branches of thn 
pulmooaiy artery, gotag to the two lid^ of the lungs; m m, the 
pulmonary veiiiB, which bring ibe blood back from Lhelungs toihe 
leftsfdeorthehiittit: n, the right aurkU; Oj the a^^n^ing vena 
cava; a, the descfjndiag: these two meet, and by their uniDD farm 
thfe right auricle; p, tho veins trorti this livet, spIe«T), and bowels;; 
i, the left coronary artflry, one of thu arteries which nourUh the 

divided into the internal and eternal arterieB of the 
headj arterieft of the face und neck, arteries of thearmsj 
etc. As the aorta descends, it g}ve% off bra^chea> aH 
along its couri*, which go to the internal organs, to 
the walls of the body, etc. All these different branches^ 
fts their proceed towards their deatination, divide and 
subdivide and inosculate or mn into each other in 
every direction, like a net (fig, 30^ ff), till they become 
extremely minute twigs, which are lost in the tissues 
of the parts to which they arediitributed, penetfating 
to the smallest musciUar and nervous filaraenti, and 
being dispersed so universally and ho numerously over 
the whole bodyj that it is scarcely possible to puncture 
any part with a fine needle, without woundinz some 
of these little vessels. These are called capillary or 
hair^aized yesaels, and collectively with those of the 
yeans, constitute the capillary system {3l3)j in and by 
which all the important changes in tJie blood are ef- 

375. The number of these capillary vessels has been 
estimated at more than one thousand to every square 
inch. Some physiologisti* have conjectured tkat there 
is another set of almost infinitely minute vessels con- 
nected with the capillary extremities, and immediately 
concerned in nourishing the several tissues, etc, 
which they call the eih^nta ; but this is mere con- 

370. It h a general 1a w of the animal organic econ. 
omyj thnt all vital action is attended with an erpea- 
diture of vital power and a waste of organized sub- 
stance (l&2)j and these are replenished bv the arte- 
rial blood* In the distribution of arterial vessels to 
the different partSj therefore^ each organ is supplied 
aiccording to the nature of iu functioa and its ? «l&tive 

Importance in the systetnj and such is the general 
and particular arrangement, that every part^ and es- 
pecially every important part, is so furnished that if 
its blood b« obacnu^«d in some of Its ressels, it freely 
flows on in others. 

377' Th* arterial vessels of the braiTi are very nu- 
merous and capacious ; and the voluntary muscles, as 
we have s^en fl92), are largely supplied with them. 
As a general fact, however, the arteries distribiited 
to the organs of organic life, ajid particularly those^ 
in which there is much vital action, and those in 
and by which important vital changes are effected, 
are lai^er and mor« numerous than those distributed 
to the organ* of animal life (lft&). The vessels of 
the heart, which is constantly in action, are propor- 
tionally very large; those of the stomach are also 
large and exceedingly nomeroua ; and those of the 
small intestine are litUe less so- Moreover, the arte- 
ries are capable of being both enlarged and diminished, 
to a considerable ^tent, without actual disease- In 
a limb which is habitual! v and vigorously exercised, 
the arteries become mucli larger, and the muscles 
more fully developed, than in the corresponding limb 
which is little employed ; aod, on the other hand. If 
the same limb be suffered to remain inaetive for a 
considerable time, the size of the arteries will be much 
diminished. In case of an injury, which renders it 
necessary to lie the principal artery of a part, the 
smaller arteries of the same part immediately begin 
to increase in size, and in a short time they become 
sufficiently capacious to supply the part with nearly 
or quite as much blood as it received before the injury, 

370. Either continuing from^ or originating very 
near, the extremities of the arterial capillnriesj those 
of the veins rise in equal or greater number ; and, 
running into each other, became larger and larger, 
till they form numerous branches, which unite to 
form a large venous trunk called the v^na cavctf or 
returning hollow. The veins from the lower and 
middle parts of the bodv, and lower limbs, form the 
ascending vena cam ,' wkidi goes up by the side of the 
great arterial trunk (fig. 2a, v v% and opens into the 
right auricle of the heart (fig. 40, 0). The veins from 
the upper part of the body, the upper extremities, and 
the head, form the d^^ccndinff ttena catfo, which opens 
into the same cavity, near the mouth of the ascending 
venous trunk (fig* 40, 9). 

379. The veins anastomose, or run into each other 
in a net*Iike manner, even more frequently than the 
arteries ; and for the same important purpose, viz., if 
the flow of the blood be obstructed in some of the 
veins, it readily turns aside into others^ and goes on 
its way. The number of branches and twigs, com- 
pared with that of the trunks, is much greater in the 
venous than in the arterial sptem ; so that, as a 
wholey the venous system is much more capacious 
than the arterial 

380. Myriads of arterial and venous capillaries, as 
we have seen (2S7), pass through the meshes of the 
great limiting membrane^ and assist in forming the 
vasculo^nervouB web upon its exterior surface* In 
this web, however, the venous capillaries seem to bo 
much more abundant than the arterial, both in the 
mucous membrane and in the skin. In the mueoua 
membrane of the alimentary canal, according to Dr. 
Horner,* * the stiperficial layer of vessels composing 
this web or plexus appears to consist almost entirely 
of a cribriform texture of veins. The arborescenca 
of the arteries is confined to the level beneath the 
venous inter texture, and is there developed to an ex- 
treme degree of minuteness, being intermixed with 
COTxe^ponding venous ramuscles, generally larger and 
more numerons than the arteries themselves*' ^ The 
external surface of the cti/i* vera, or true skin, pre- 
sents as it were an outline of tlie same arrangement ; 
the venouBj reticular intertexture appearing bro&der| 

* S«e AppwidiXy Kot* A. 



not quite to perfect, and more ihallow, and forming 
the papilla.' 


381. I have said (378;), that the veins arising from 
the venous capillaries in all parts of the body, run 
into each other like a net, gradually increasing in 
sise till they finally unite to form the great ascending 
and descending venous trunks which open into the 
right auricle of the heart. But there is a remarkably 
peculiarity in the arrangement of the veins arising 
from the abdominal viscera. All the veins arising 
fnurn the venous capillaries of the stomach, tiie spleen, 
the pancreas, the omentum, the small intestine, and 
the ascending and transverse colon, run together in 
the manner already described (378), and form the 
three large veins called the coronary vein of the stem- 
ach, the splenic, and the mesenteric veins. These, 
instead of advancing directly to the vena cava, unite 
and form a large venous trunk, which proceeds ob. 
liquely upward to the right, and plunges into the Uver, 
where it suddenly divides into branches, which are 
ramified in the manner of an artery (fig. 21), and 
wliere in fact it takes the place of an artery, being 
distributed in the same manner, and hxddingthe same 
relations to the secreting surface, or the mucous mem- 
brane of the ducts, that the principal artery does in 
other glands. This peculiar arrangement of veins 
constitutes what is called the system of the vena 
TO^TJEy or the PORTAii system; and where these 
veins terminate in the ramifications of the biliary 
duct, other venous capillaries arise, which, running 
into each other, form the hepatic veins ; and these, 
receiving the blood from the j>ortal veins, and from 
the hepatic artery, convey it to the vena cava 

382. The portal system has an appendage which 
has hitherto exceedingly perplexed physiologists, and 
been the subject of a great diversity of experiment 
and speculation. It is called the spleen, and is situ- 
ated in the upper and back part of the abdominal 
cavity, on the left side between the diaphragm and 
the left kidney (fig. 28, «). It is attached to the dia- 
phragm, the stomach, and the ascending colon, in a 
loose manner, by folds of the peritoneum, and by a 
great number of vessels ; and hence the left extremity 
or large end of the stomach, is called the splenic por- 
tion. The spleen is extremely spongy or vascular, 
bein^ formed almost entirely of blood-vessels, lym- 
phatics, and cells, woven together by cellular tissue, 
and surrounded by a very firm sero-fibrous membrane. 
Its artery ramifies in a peculiar manner, and abrupUy 
expends itself on the tissues of the organ. Its veins, 
which are proporHonaUy larger than in any other part 
€f the botfyf arise from the cells, and empty into the 
vena norts ; or, rather, they constitute, as we have 
seen (381), a part of the roots of the portal trunk. 
Its lymphatics are very numerous. Its nerves come 
hpm the splenic plexus of the nerves of organi<; life, 
and are very small. The form of the spleen is ellip- 
tical or oval. Its 9ize varies much, not only in differ. 
ent individuals, but also in the same individual at 
different periods, and inconstantly. As a general 
statement, however, it is, in an adult, about four 
inches long, three broad, and a little less than one 
thick. Its weight varies as much as its size, but on 
an average is about eight ounces. It would be a tedl- 
ooi and unprofitable task to recite the various opinions 
which have been advanced concerning the use of tiiis 
OKgan. The conclusions to which I have arrived, after 
a careful examination of them all, will be presented 
when 1 come to speak of the functions of the liver 
and the vena ports (450). 

'3SSL The arteries are composed of three coats. The 
CGKterior one is a dense cellular tunic. The middle 
one, called the muscular coat, consists of transverse 
drcnlar fibres of a yellowish color, which, thoiufh 
they differ in appearance from the ordinary muscular 

tissue^ are contractile like the muscular fibre. The 
inner coat is a very smooth, thin, transparent mem- 
brane, which has no appearance of fibres, and is ooq« 
tinuous with that which lines the cavities of the heart. 
The veins, according to some anatomists, have but 
two coats. Others, perhaps more correctly, say three. 
Of these, the outer one is a dense cc^ular coat, and is 
very strong. The middle one is composed of long, 
itudinal fibres resembling th^ circular fibres of the 
arteries. The inner coat is exceedingly thin and 
smoojth, and is very similar to diat whicn lines the 
arteries and heart. Some anatomists think it ia a 
continuation of the same. This coat, in most or all 
the veins in which the blood ascends against gravity, 
is frequently folded so as to form a species of valves, 
which favor the course of the blood towards the heart, 
but obstruct its course in a contrary direction. 

384. The nerves which enter into the structure of 
the blood-vessels, and preside over iheir functions, we 
have seen (219, 231), are from the ganglionic system 
(228). Th^ much more largely abound in the capil- 
lary vessels, in and by whida lOl the important vital 
changes are effected in the blood, than in the larger 
trunks and branches (231). 


385. There is another set or system of capillary 
vessels, of which I have offcen spoken, remaining to 
be described, called the lymphatics. These vessds 
are extremely minute, so that in many parts they can- 
not be detected without the help of the microscope, 
and even with this help they have not yet been found 
in the brain and some other parts, where there is rea- 
son to believe they exist. In their texture they con- 
siderablv resemble the veins. They have two coats, 
of which the external one is cellular, and capable of 
considerable extension ; their inner coat is frequently 
folded, so as to form valves like those in the veins, 
and their walls are so thin that these folds give them 
the appearance of being jointed (fig. 41, 42, 43). 

Fig. 41. 

Fig. 42. 

Fig. 43. 

The lymphade yessesls greatly enlaxgad, ihowing tbeir Jointed 
appMurance. 42 shows the interior yalvee; 48 shows thoTessels 
running into each other and their passage through a gland. 

These vessels rise in immense numbers from almost 
every internal and external surface and substance of * 
the human body, so that there is scarcely a particle of 
matter in the whole incorporated system which can- 
not be reached by them. Myriads of than rise from 
the skin and mucous membrane, and their extremities 
form a part of the vasculo-nervous web or plezua 



(287), on the exterior surface of this great limiting 
membrane (337). Many of these vessels lie immedi- 
ately under the external skin (fig. 44) ; others are 

Fig. 44. 

Shows tbe lymphatics, e, of the thigh, lying under the skin ; 
with their glands or ganglions, a, at the groin. 

buried in the substance of the organs, and others 
course along the internal membranes. In every part 
they run into each other frequently, in a net-like 
manner, but they everywhere continue nearly of the 
same size (fig. 43). 

386. At certain points the lymphatics pass through 
bodies peculiar to themselves, called tne lymphatic 
glands or ganelions (fig. 43). These are small flat- 
tened bodies of an oval or circular shape, of different 
sizes, varying in diameter from one twentieth of an 
inch to an inch. They are extremely vascular, and 
appear to consist of inextricable plexuses, of lympha- 
tics, blood-vessels, and nerves. These glands are situ- 
ated in different parts of the body, but they mostly 
abound in the thorax and abdomen. Leaving these, 
the lymphatics^ proceed in a direction towards the 
heart, and, as it were, converffe from all parts of the 
body so as to pour their contents into tubes, which 
dpen into large veins leading to the heart, near the 
bottom of the neck. Most of them terminate in a 
tube about the size of a goose quill, called the tho- 

racic duct, which commences in the abdominal Cavity, 
and passes up by the side of the great arterial trunk, 
in front of the spinal column (fig. 45, d d), and, hav- 
ing ascended a short distance above the large vein of 
the left arm, it turns down and opens into that vein 
(fig. 45, «), at the angle formed by the junction of 
the large vein of the head with that of the arm. The 
lymphatics of the right side of the head and neck, of 
the right arm, the right lung, and the right 
portion of the diaphragm and liver, terminate 
in a short tube, which opens into the correspond- 
ing vein of the arm on the right side. Besides these 
connexions with the venous system, many of the lym- 
phatic vessels, as capillaries, empty into the veins in 
the tissues of the organs ; the lymphatics of the ab- 
domen terminate abundantly in the branches of the 
vena portae, and also in several other veins ; and lym- 
phatic vessels terminate in veins in the lymphatic 

Fig. 45. 

Shows the spinal oolnmn, with d d, the thoracic duct, ascend* 
ing in front ol it, and entering the subclavian vein at s. 

387* The lymphatic system, though essentially the 
same in allits parts, so far as anatomical structure is 
concerned, seems to perform a diversity of function, 
and therefore it is divided, in the descriptions of ana- 
tomy and physiology, into two classes or orders of 
vessels : the one consisting of the lymphatics proper, 
or those employed in elaborating lymph, and convey- 
ing it from every part of the body to the thoracic 
duct ; the other consisting of the lacteals, or those 
employed in elaborating chyle from the contents of 
the alimentary cavity, and conveying it also to the 
thoracic duct. 

388. The lymyhatics proper, as I have said (385), 
pervade the whole body, arising in great numbers 
from the external skin, from aU the internal mem- 
branes, vessels, and cavities, and from the substance 
of all the organs. But the lacteals arise only frmn 



Pig. 4d. 

J A U A piece of n smill intcstmu ; b b h b are the Euperflciftl 
l&cteaU ; f c c is the meaentefyt h del;ciit« but firm membrane, 
CQTiiisting <if two layers, by which the intwiinca am tonoected 
with the ipine, and within the fblda of which the deep-seated lae- 
t^A\% pAS4 ', ddd and e a e^ the two Hts of abAorbent glands ; //^ 
the rect^ptaclc of the chyle ; j, the thornoic duct; i i, the Ijtn- 
phatici, cflraing &om difTeteJit parU of thft body; J^, the aoitaj 
the ^eat arieryn 

the tnueoua membrane of the alimentary canal, and 
principally from the mucous membrane of the small 
intattine. Indeed, physiologists generally speak of 
them u arigmg: wholly frocn this section of the canal, 
and u being much more numerous in the upper than 
in the lower portion of it. But it must be remem- 
bered that there is no appreciable difference in struc- 
ture between a lacteal and a lymphatic vessel, and 
that aU which distinguishes the one froto the other 
is, that the one, in the regiiiar performance of it* 
office:, elaborates and ponveys chyle, and the othor 
J™ph, which in many respects nearly resembles chyle- 
As a general statement, they are all assimilating or- 
gans ; and wherever they may be situaCedj if thefj 
elaborate chyle from alimentary »ubitance8j and con- 
vey it to the thoracic duct, they are ju fact lacteala. 
And it is very certain that chyle maj^ be, and there is 
reason to believe that it regularly la^ elaborated by 
some of theae veasela from the alimentary contents of 
the stomach. Experiments on animals have proved 
that they can be sastained for months at least with 
the pyloric orifice of the stomach (341) completely 
closed by a ligature, so that the food received into the 
gastric cavity cannot pass into the ttuall intestine ; 
but the process of chymiiicntion and chylification are 
effected by the stomach and its lacteals^ and the excre- 
mentUious matter is evacuated by the month (471}» 
There have also been instances of human beings who 
have been sustained for years in this manner, the py- 
loric orifice being entirely closed by diseaseof the parts. 
*G«i. Grose, who aerved under the Duke of Cumber- 
land, in Flanders,' saya Sir Everard Home, ' had no 
passage through the bowels for thirty years ; yet he 
had a g^Kid appetite, and ate heartily, and was a healthy 
and able-bodied man. In two hfturs after eating, he 
threw up the contents of his stomach remaining un- 
disposed of.' Chyle may he, and probably is, elabo- 
rated to some extent also from the large intestlnOj or 
colon (338). It is not, therefore, strictly correct to 
say that the laoteals arise only from the small intes- 

tine. For important reasons, however, it is never- 
theless true that they mostly abound in this s»^ 
tion oi the alimentary canal, and are most numer- 
ous in the upper two thirds of this section, or In 
the duodenum and jejunum (333^), Leaving the 
alimentary canal (lig. 4fj', a a a), the kcteals (%, 
46, b h\ proceed across the mesentery (fig, 33, and 
46, c c) (350), converging towards the back-bone, 
and having passed through a number of their 
ganglions (fig. 4&, d e) here called the mesenteric 
glands, they terminate In the portion of the 
thoracic duct (iiSC) ciiUed the receptacle of the 
chyle (fig. 45, /), According to some anatom- 
ists, most or all the lacteals traverse a portion of 
the liver before theji reach the thoracic duct. 

309. The lymphatic system may be considered 
as an appendage to the venous system, furnishing 
it with all tiie assimilating materials hy which 
#ie body is noiLrished, as well as conveying to it 
the elfete substances which are to be diminated 
froui t^io vital domain. These two systems are 
connected, as we have seen (386), at several points, 
and the structure of the lymphatic vessels much 
resembles that of the veins (365), Moreover the 
venous capillaries and the lymphatics appear, to 
some eitentj to reciprocate in function, and tha. 
lymphatics always empty their contents into the 

390, In the lymphatic system, as in the &rt&, 
rial and venous, the nerves of organic life supply 
the nervous tissue of all the vessels, and preside 
over all their functions (230) ; and in these ves- 
sels, as we shall see, some of the most important 
vital changes take place. 


301, Concerning the agencies and forces employed 
m the circulation of the blood, and other £uJds in the 
vessels just deacribed, physiologists have differed 
widely in opinion. Some have asserted that the heart 
alone exerts all the force by which the blood is cir- 
culated, and that the arteries and veins have no other 
agency in the general function than as elastic, con- 
ducting tubes, to adapt their capacity to the volume 
of blood which they contain \ and accordingly the ad- 
vocates of this theory have denied all contractility to 
the arteries, and estimated the contractile power of 
the heart as equal to many hundred pounds. On the 
other hand, It is crmtended by others, that the heart 
simply injects the blood into the arteries with a very 
small force, and the arteries, by their active and vigo- 
rous contraction, carry on the circulation as in those 
animals which have no heart. Others, again, with 
more correctness, take the middle ground between the 
two extremes 

3iJ2, According to the best experiments and esti- 
mates which have been made on this point, the left 
ventricle of the heart acts with a force of ilx pounds 
on the square inch. This ventricle, when distended, 
has about ten square inches of internal surface, and 
consequently the whole force exerted by it in throw- 
ing the blood into the aorta* is about sixty pounds- 
That the arteries are very elastic, and that they have 
the power of adapting their capacity to the quantity 
of blood in them^ is I believe sulmitted on dJ!! hands ; 
and it is generally acknowledged that when animals 
bleed to death, and at ho after the heart has ceasied to 
act in what is called natural death, the arteries con- 
tinue to diminish their capacity till all the blood is 
pressed out of them, 

393, We have seen (376) that It is a general law of 
the organic ecoidf^y^ that all vital action is attended 
with an expenditure of vital power and waste of or- 
ganised substance, and that these are replenished by 
arterial blood. It Is also a general law of the organic 
economy, that all increai^ed action of a part is attended 
with an increased flow of blood to the part. But this 



local inerease of blood does not depend on the action 
of ti^e heart, nor on the general action of the arteries. 
It is the effect of the special action of the arteries of 
the part acting under the influence of the special ceti. 
tre (219) whidi presides over the organic iiinction of 
the part. It is very evident, that, in particular 
organs, the blood-vessels, and especially the arteries, 
are to some extent under the control of the special 
centres which preside over the functions of those or- 
gans. Thus, when food is introduced into the stom. 
ach, the vessels of that organ soon become injected, 
sometimes even to turgescence, without any increased 
general action of the heart and arteries. The nerves 
of organic sensibility (230), perceiving the presence 
and qualities of the food, immediately inform the spe- 
cial presiding centre, and this instantly throws \U 
si mmating influence upon the arteries belonging to 
the stomadi, and causes them to fill themselves, and 
to inject the secreting vessels with an increasing quan- 
tity of blood ; and if the substance introduced into th e 
stomach be of a highly offensive character, the quan- 
tity of blood pressed into the vessels is often very ck^ 
eessive, producinc^ great congestion. 

394. Both the heart and the arteries, therefore, are 
actively concerned in the general circulation of the 
blood, while the special increase of blood in particular 
parts depends entirely on arterial action. At every 
contraction of the left ventricle of the heart, the aorta 
is somewhat dilated ; but it instantly contracts on the 
blood, and presses it onward through the branches into 
the capillary extremities (374), the blood being pre- 
vented from returning into the ventricle by the valves 
at the mouth of the aorta (369). The branches act 
in the same manner as the main trunk. But both 
the aorta and the large branches issuing immediately 
from it, are probably much less active in the function 
of circulation than the smaller twigs, and especially 
the capillary vessels. 

395. In regard to the venous circulation, some 
physiologists have thought that the force exerted by 
the heart is sufficient to effect the motion of the blood 
in the veins. Others have supposed that the propel- 
ling action of the capillary vessels, the throbbing of 
the arteries against the veins, the suction of the heart 
by the dilatation of its auricles, and atmospheric 
pressure connected with respiration (365), are all con- 
cerned as moving forces in the venous circulation. 
But the texture and construction of the veins (383), 
and the physiological analogy of the whole vital eco- 
nomy, snow that the veins as well as the capillary 
vessels possess the power of propelling the fluids which 
drcolate in thian. 


396. The parts which remain to be described, and 
which in the order of development (174) appear later 
than the internal organs, are the apparatuses to which 
the nerves of special sense are distributed,, and the 
hair and nails. The organ of touch I have already 
described (242, 253, 287). It is extended over the 
whole external surface of the body, and in fact may 
be said to pervade the whole body, because at every 
point we are exposed to the action of those tangible 
properties of things which may prove injurious and 
destructive to life. In man, however, the ends of the 
fingers are more particularly appropriated to the 
voluntary function of touch or feeling, and here moit 
thickly cluster those little tufts or velvety eminences 
formed principally of the minute extremities of the 
nerves of sense, called the papillsB (287). The sense 
of touch or feeling is the primary animal sense, and 
exists in a greater or less degree in %very living ani* 
mal r294). It is determinately established npon the 
constitutional laws of relation existing between the 
living body and external substances and things, and 
with strictest reference to the physiological interest of 
the body. 


397. The nerves of taste, or the gustatory nerves, 
I have said (254), are distributed to the mouth and 
throat ; but the papillsB in which thdr extremities 
Unminate most largely abound in the mucous mem- 
brane which covers tSbe end of the tongue. This 
Heaxe is founds on the alimentary wants of the vital 
ettrtxamy^ and lifet^minately established on the con« 
stitutional laws of relation between the physiological 
interests of the body and its appropriate alimentary 


398. The sense of smell (294) is nearly allied to 
"tibat of taste, in the character and extent of its func- 
tional relations and responsibilities. It is founded on 
the respiratory and alimentary wants of the vital eco- 
nomy, and determinately established on the constitu- 
tional laws of relation between the physiological inter- 
ests of the body and the qualities of external things 
which may affect those interests, through the func- 
tions of respiration and alimentation, or through the 
medium of the lungs and stomach. 

309. The olfactory nerves, or the nerves of smell, 
I have described (251, 252). They proceed from the 
centre of animal perception (280), and terminate in 
the vasculo-nervous web (287), on the exterior sur- 
face of the mucous membrane which lines the nostrils 
and the cavities connected with it. There are four 
principal cavities, two of which are situated in the 
upper jaw (one on each side of the face), and two in 
the prominent part of the frontal bone, directly above 
the eyes ; and all of these communicate with the nos- 
trils. Whether the sense of smell is as extensive as 
the mucous membrane which lines these various cavi- 
ties and passages, or is limited to the superior part of 
the nasal fosse, is a question on which physiologists 
are not agreed. Some experiments and pathological 
facts seem ta prove that the olfactory sense is limited 
to the superior part of the nasal canals where the 
olfactory nerve is mostly distributed, while compa- 
rative anatomy and physiology favor the contrary' 
opinion, the cavities being most largely developed in. 
those animals which are most remarkable for their 
power of smell. 

400. It is essential to the integrity of the faculties 
of taste and smell, that the parts to which these senses 
belong should be continually moistened. If by dis- 
ease or otherwise th^ mucous membrane of the mouth 
and nose becomes perfectly dry, the senses of taste 
and of smell are for the time entirely abolidied. 
Hence, in a healthy state and condition of these parts, 
the mucous membrane is at all times moistened and 
lubricated by its own exhalation and secretion (339). 
But this is not peculiar to these parts. Throoghoat 
the whole extent of the mucous membrane and exter- 
nal skin, the same condition is essential to the func- 
tional integrity of the nerves and vessels whichrform 
the vasculo-nervous web on the exterior surface (287)* 
The situation of the mucous membrane in the nasal 
cavities, however, renders it peculiarly liable to be- 
come dry, and hence there seems to be a necessity to 
a very cc^ious supply of lubricating fluid ; and it may 
therefore be true, as has been suggested by some 
physiologists, that the office of the cavities associated 
with the nasal canals is to secrete mucous for thote 


401. The sense of hearing and the sense of tigikt 
are founded on the general wants of the organic tyi-' 
tern, with whatever powers and capacities it may pot* 
BOSS, and with regard to the most extensive rdations 
(294). Thev minister not only to those wants which 
arise from the operations and conditions of the 'V'ital. 
economy, but also to the mental and moral wants,* 
whether more or less comprehensive and diversified. 
They are therefore of a higher order of functional 



character, and are not susceptible of being sensualized 
and depraved like taste and smell. 

402. The organism specially appropriated to these 
senses is exceedingly complicated and difficult to be 
described in an intelligible manner. The apparatus 
which constitutes the organ of hearing is perhaps the 
most intricate and complicated piece of organic me- 
chanism in the human body. It has been the subject 
of an immense amount of observation, investigation, 
and experiment. Its anatomy has been studied and 
described with great minuteness and accuracy, and 
yet at the present moment very little is known of its 
physiology, except the bare fact that it is the organ of 
hearing. I shall therefore only give a very brief and 
general description of this organ, and refer the curious 
reader to the minute anatomists for further informa- 
tion respecting it. 

403. * The organ of hearing may be divided into the 
outer, the inner, and middle parts, and the auditory 
nerve (fig. 47). The outer part consists of the exter. 
nal ear and the tube which leads to the membrane of 
i^e tympanum. The external ear is composed chiefly 
of cartilage, covered with a delicate skin, and supplied 

Fig. 47. 

A nap of the ear. 

a, the extern^ auditory tabe; b, the mem- 

e, ' 

brane of the tympanum; e, the Bottachian tube; tf, the ham< 
nor; e, the anvil; /, the round bone; g, the itiirup; h, the 
Ofral opening; it the semicircular canala; Jt the Testibule; k, the 

with nerves and blood-vessels. When well formed, it 
Inclines a little forward, and is admirably adapted to 
eoUect sound, which it transmits through the tube 
that leads to the membrane of the tympanum (fig. 47, 
a). This tube is nearly an inch in length, and is 
fixrmed in part of cartilage, and in part of bone. It 
baa a number of small glands or follicles which secrete 
the wax (ZSS), and its entrance is guarded by stifiT 
ludrs, to prevent insects and other fomgn bodies from 
entering. When it is recollected, however, that the 
membrane of the tympanum has no opening, it must 
he apparent that tne apprehension which is so often 
exprMsed lest insects should penetrate into the head, 
is wholly groundless. 

404. ^ The middle part of the organ of hearing 
embraces the tympanum and its membrane, theimafi 
Inmes of the ear, and the Eustachian tube (340). The 
membrane of the tympanum is situated at the bottom 
of the external passage or tube (fig. 47, 6), and is cov- 
ered on its extmor by a thin delicate skin, the same 

that lines the tube. Its inner surface is covered by a 
mucous membrane, and a nerve called the chord of the 
tympanum passes over it. To this inner surface slso 
is attached one of the small bones of the ear. This 
membrane is placed obliquely, inclining downwards 
and inwards, and is terse, thin, and transparent. 

405. ' The tympanum is a cavity situated between 
the external and internal ear. It is of an irregular 
cylindrical form, with several openings, some commu- 
nicating with the internal ear, and one which is the 
termination of the Eustacian tube. It also contaiiis 
the four little bones of the ear, called the hammer 
(fig. 47, c/\ the anvil (e), the round bone (/), and the 
stirrup {g). These bones are all connected together; 
the end of the hammer is attached to the membrane 
of the tympanum, and the stirrup is placed over an 
opening which leads to the internal ear. Muscles of 
very small size are inserted into these bones, and move 
them in various directions. The Eustachian tube (o) 
leads from the cavity of the tympanum to the back 
part of the throat (340). It is about two inches in 
length, partly bone and partly cartilaginous, and is 
lined by a mucous membrane. Its two extremities 
are not of the same size, the one opening 
into the throat being somewhat larger than 
the other. 

406. ' The internal ear is situated in a part 
of the temporal bone, near the base of the 
skull, which, from its stony hardness, is called 
the petrous portion. It is composed of three 
parts ; the cochlea (fig. 47, k), the vestibule 
( j), and the semicircular canal (t). The coch- 
lea is so called, from its resemblance to the 
shell of a snail. It is situated near the en- 
trance of the Eustachian tube, and is the 
most anterior part of the internal ear. It 
communicates with the cavity of the tympa- 
num and the vestibule. The vestibule is situ- 
ated in the central part of the internal ear, 
and is, as its name imports, a sort of porch or 
entry, which communicates with all ike other 
parts. By means of the oval opening (the 
foramen ovale) it communicates with the tym- 
panum, and over this opening is placed the 
smidl bone called the stirrup [stapes). It 
has communications also with the cochlea, 
the semicircular canals, and internal auditory 
tube, the one through which the auditory 
nerve passes to the internal ear on its cnut 
from the brain ; and it is through the openings 
which lead from the vestibule to the mteniAl 
auditory tube, that the branches of the audi- 
tory nerve fQ to the various parts of ^e in- 
ternal ear. The three semicircular canals are 
situated behind the cochlea and the vesti- 
bule, and they all terminate in the latter* 
They contain a dark grayish s«ni-fluid sub- 
stance, the use of which is unknown. 
^ The auditory nerve (351, 252^ passes into the 
internal auditory tube, and is subdivided into numer- 
ous small filaments, which pass through the minute 
openings, and are distributed to the semicircular 
panals, the cochlea, and the vestibule, terminating in 
the form of a pulp.'* 

408. In regard to the office of these several parts, 
in the general function of the organ, nothing is known 
with certainty. The membrane of the tympanum 
has frequently been ruptured without impairing the 
faculty of hearing. Ail the small bones of the ear, 
except the stapes, have also been removed by disease^ 
and still the ^culty of hearing remained. These 
facts, however, while they prove that those parts are 
not immediately essential to the function of hearing, 
do not prove that they are not most perfectly adaptal 
to the permament economy and functional int^rity of 

• Hayward'i OutUnes of Human Physiology. 




the or^n. The membrnne of tte tympaJium is prij- 
bablf designed roaiuly to shut out foreign lubstances 
fram the inner chatnbert of the ear, and thus keep 
the auditory nerre, which is expanded into tbrae 
cEambertj in the most deli cute and suEfCeptible condi- 
tion, and at the same time it ia mast perfectly fitted to 
tranimit vt&rationa to that nerve* 

ConcEirning the function of the auditory and other 
organs of JienAe I Kb all ipeak more fully when treating 
on the Intellectual aiid morU pow^r^, and on tbe laws 
of relation. 

ORGAN OF Smill'p 

409. * The apparatus which consti lutes the organ 
of vision is somewhat less complicated than that of 
heanng^ and the uses of its rariotis part* are much 
better understood. The eye is an optical instrument 
of the most perfect construction. It is of a globular 
form, composed of a number of huraorSj so called^ 
which are covered by membranejt, and enclo^ied in 
several coats (fig. 48). These humors are culled the 
vitreoui (c), the crystalline (6), and the aqueous {a). 
The vitreous, which takes Its name from its resem^ 

Fig. 48. 

A sectioa of the human eye. a, the aqueoas humor ; 5, the 
crystalline lens; c, theyitreoushimior; d, is an object from which 
the rays of light go off, and as they enter the eye, they are re- 
fracted by the diffen 
on the retina. 

fferent humors, and form an inyerted image, e, 

blsnce to melted glass, is situated in the back part of 
the eye, and constitutes the greater portion of the 
globe. It is of the consistence of the white of an egg, 
and is contained in numerous small cells, formed in 
a membrane of great delicacy, which also covers it. 
On its anterior surface there is a slight depression, 
and in this is situated the crystalline humor or lens 
(fig. 48, b). This is a body of considerable thickness 
and strength, an^ has the foim of a double convex 
lens ; the convexity of the two sides, however, is not 
the same. It is placed in a perpendicular direction 
immediately behind the ptipil, and is kept in its situ- 
ation by a membrane which is called its capsule. 
In front of the crystalline lens, and occupying the 
whole of the anterior part of the eye, is the aqueous 
humor (a), the only one of the three which is properly 
called a humor, tt is composed principally of water, 
with a few saline particles, and a very small portion 
of albumen. A curtain with an opening in its cen- 
tre floats in the aqueous humor, but is attached to 
one of the coats of the eye at its circumference. This 
curtain is called the iris, and the opening in it is the 
pupiL It derives its name from the various colors it 
has in different individuals ; and it is the color of the 
iris that determines the color of the eye. Some have 
thought the iris to be a mere continuation of one of 
the coats of the eye ; others have supposed it to be a 
peculiar texture ; and others again are of opinion that 
it is formed in part from one of the coverings of the 
eye, and that it has also a layer peculiar to itself. 
The back part of the iris is called the uvea. The iris 
divides the space between the crystalline lens and the 
front of the eye into two parts, called the anterior and 
posterior chambers, the former of which is much 
larger than the latter. All the light admitted to the 

eye paBses ih rough the pupil, which is dilated and 
contracted bv the radiating and circular muACular 
fibres of the Iris, accnrdlng to the intensity of light, 
the p<>wer of the eye, etc. 

410. * The eye has three coats or coverings. The 
outer, which la called xh& sclerotic, h a Hrm fibrous 
membraue (IG!>), which serves to defend the eye from 
injury, and ioto which the muscles that move it in 
various direations are insarted. It extends over the 
whole of the eye, except the fore part, which is covered 
by a ti^nsparent membrane. It is the sclerotic coat 
which is commonly called the white of the eye. Within 
the sclerotic coat is situated the choroid coat. It is a 
thin delicate membrane, composed mostly of b]cM>d- 
vessel* and nerres. It is loosely attached to the scle- 
rotic coat^ which ft cover?, and h of the same form 
and extent. On the inner surface of the choroid coat 
is found a dark substance called the black pigment 
which is of great importance iii tiie function of vision. 
41 L '^The inner coat of the eye, if it be not an ex- 
pansion of the optic nerve, is composed of nervous 
filaments, and is called the retina (252), It is of the 
same extent as the other coats, surrounding the whole 
globe of the eye, except the circular opening in 
front, to the edge of which the circumference of 
the iris is attached by a band called the ciliary 
ligament, and over which is placed the convex 
transparent membrane, which, from its resem- 
blance to horn, is called the cornea.' 

412. The optic nerves have been fully describ- 
ed (251, 252). < They do not enter the eyeballs in 
the centre, but a short distance from it towards 
the nose. The balls are situated in deep bony 
sockets, with prominences above, on which, are 
placed the eyebrows. They are furnished with 
lids, which can shut so closely as to exclude not 
only foreign bodies, but even light. There is also 
an apparatus by which the external surface of the 
balls is moistened, and foreign particles washed 
away. The eyelids have a thin delicate skin on 
the outside, muscular fibres beneath, and a cartil- 
^ — age on their edges. They are lined by a mucous 
membrane which passes from them over the anterior 
part of the eye, and is called the tunica conjunctiva, 
because it ii the tunic which connects the eyeballs 
with the lids. It is loosely attached to the eyelids, so 
as to allow free motion in all directions. In the edges 
of the lids are numerous small glands or follicles which 
secrete an unctuous substance that is probably ex- 
pended on the eyelashes.* * 

413. The fluid which continually moistens the eyes 
is secreted by the lachrymal glands, which I hare de- 
scribed (334, 345). These glands are situated within 
the orbit, at the outer angle of each eye (fig. 49, a), 
and eonstantly supply the eyes with' moisture, not 
only when they are open and in action, but also when 
closed and quiet in sleep. The fluid thus secreted, 
having performed its office, passes from each eye 
through two small openings (one in each lid), called 
the puacta lachrimalia (fig. 49, c c), and is thence 
conveyed into the nose by a cansd on each side, called 
the nasal duct (fig. 49, d e), which is lin^d by a m^u- 
cous membrane. These canals, from inflaqimatioii 
and other causes, frequently become obstructed* and 
then the moisture accumulates in the eyes, till it flows 
over the under lid. When the lachrymal glands are 
much excited by irritations of the eyes or nose, or Jhy 
strong emotions of the mind, or morbid sensibilities, 
they pour their fluid into the eyes, far more rapidly 
than the nasal ducts ean convey it to the nose» and 
consequently it overflows the under eyelids, and run/i 
down upon the cheeks, and is called tears. 
. 414. Each eye has six muscles, which are attached 
to the outer coat, and which turn it in every cUrection. 
These muscles are among the most curious parts o$ 

* Hayward's Outlines of Human Physiology. 



the visual apparatus. The nerves which convey the 
•timulus of vohintary motion to these muscles have 
been described (248, 249). Those which impart the 
sense of touch or feeling to the eyes, ears, nose, and 
mouth, are from the trifacial or the fifth pair of the 
old anatomists, and have also been fully described 

Fig. 49. 


a, the lachrymal gland ; b, its several ducts, to convey the tears 
to the eye ; c c, the puncta ; d e, the nasal duct. 

415. So far as the eye is considered as a mere opti. 
cal instrument, the philosophy of vision is easily 
understood and explained ; but when considered as a 
living animal organ of visual perception, the philoso- 

Ehy of its function is much more intricate, and has 
Itnerto greatly perplexed the learned, and given rise 
to many ingenious speculations and theories ; none of 
which, however, has been free from insuperable ob- 
jections. It is not consistent with my general plan 
that I should enter extensively into an explanation of 
the mechanical or physical philosophy of vision. The 
properties and laws of light and other principles be- 
longing to the science of optics must be studied else- 
where ; but the physiological and psychological phi. 
losophy of vision I shall endeavor to explain fully 
when I come to treat on the functions of the intellec- 
tual and moral faculties. 

4X6. It is a matter of common knowledge, that light 
is the medium of vision. If any one will take one of 
the classes of a pair of spectacles of considerable mag. 
nifymg power, and cut a hole in a windbw-shutter, 
just large enough to receive the glass, then close the 
shutter^ and exclude all light from the room, except 
what passes through the spectacle glass, if the sun is 
shining brightly, the rays of light will be seen in the 
darkened room, passing from the glass, and converg. 
ing or drawing together, till they all meet in a point 
or focus, and then diverging or spreading out beyond 
this point, the diverging rays forming exactly the 
same angle at the focal point that the converging rays 
do. At this focal point all the rays coming through 
the glass cross each other, so that the top rays at the 
glass are the bottom ones beyond the point, and the 
bottom rays at the glass the top ones beyond the 
point ; and, in the same manner, all the rays cross at 
the point. Now if a sheet of white paper be placed a 
little beyond the focal point, a beautiful miniature 
image will appear upon it, of the trees, animals, or 
whatever else the rays of light may come from, which 
pass through the glass ; and this image will have all 
the colors and hues of the objects from which the rays 
of li^ht are reflected. But the image upon the paper 
will be upside down, and turned side for side, and 
this will be caused by the crossing of the rays of light 

at the focal point ; and the rays of light are made to 
cross each other by passing through the glass in the 
shutter, which is thicker in the centre than at the 
circumference, and, being a more dense or solid sub- 
stance than the atmosphere, bends the rays towards 
each other as they pass through it. The rays will be 
bent towards each other more or less in passing 
through the glass, according as the glass is more or 
less convex, or in proportion as the centre of the glass 
is thicker than its edge at the circumference ; and, 
consequently, the more convex the glass, the sooner 
will the rays which pass through it come to a point 
and cross each other. And if instead of a spectacle 
glass, a small glass globe filled with water be placed 
in the hole in the window -shutter, the rays will cross 
and diverge before they get through it, and the image 
will be thrown upon the back part of the globe. 

417. This is a brief description of what is called a 
camera obscura, or darkened chamber, which is con. 
sidered the best illustration of the eye, and of the 
physical philosophy of vision. The interior of the 
eye is the darkened room ; the cornea is the perfectly 
transparent window glass ; the iris is the shutter ; 
the pupil is the hole through which the rays of light 
enter ; and the aqueous, crystaline, and vitreous hu- 
mors, constitute a lens of so great a convexity, that 
the rays cross and diverge before they get through 
the globe, and throw their inverted image upon the 
retina (fig. 48), where, according to the received the- 
ory of vision, the mind perceives it, not as the image 
of external things, but as the things themselves, which 
the judgment, somehow or other, contrives to get 
right end upwards. But of this, more hereafter. 

418. Sometimes, either from the shape of the eye- 
ball, or from the shape and situation of the crystaline 
lens, the rays of light cross too near the cornea (411), 
and the image upon the retina is confused and indis- 
tinct. This is the case with near-sighted people. 
When the eye becomes enfeebled by old age, or dis- 
ease, either from the falling back of the crystaline 
lens, or the flattening oi the ball, . the focal point is 
formed too near the retina, and by this means also 
the image is rendered imperfect and confused. In 
the former case, spectacles with concave, and in the 
latter with convex glasses, assist the eye in forming 
its focus at the proper distance from the retina ; the 
concave glasses, by spreading out the rays before they 
enter the pupil, and thus preventing their crossing 
so soon after they have entered ; and the convex 
glasses, by bringing the rays nearer together before 
they enter the eye, and thus causing them to cross 
sooner after they have entered. In the eye, however, 
as in every other part of the vital organism, the phy. 
siological powers are always impaired by a dependence 
on artificial means ; and though it may sometimes be 
convenient, and even necessary, to have recourse to 
the use of glasses, to regulate the focal distance of the 
eye, yet it is certain that thousands of eyes are per- 
manently injured, where one is benefited, by such 

419. The eye, in a healthy and vigorous state, un- 
doubtedly has the power of adjusting its own focal 
distance, either by the movement of its crystaline lens, 
or in some other manner ; and if man were always 
obedient to the laws of his nature, he would never 
need artificial means to improve his vision, though 
his life were prolonged to a thousand years. But it 
must ever be remembered that neither the eye, nor 
any other part of the living body, can be diseased or 
cured independently of the common vital economy of 
the whole organized system ; and that the physiolo- 
gical interests of each particular part are inseparably 
connected with those of every other part ; so that the 
organs of sight, of hearing, of smell, of taste, and of 
touch, and all the other constituent parts of the liv- 
ing whole, are dependent for their individual welfare 
on the common weal of the general assemblage. 




420. The hair and nails are generally spoken of as 
appendages of the skin, but they are as dependent on 
an appropriate organism, consisting of vessels, nerves, 
etc., for their production and sustenance, as any 
other part of the living body. Every hair has its 
root, which is situated immediately under the skin, 
and consists of a small oval pulp, invested by a sheath 
or capsule, and supplied with vessels and nerves. The 
shaft which rises above the surface of the skin consists 
mostly of a horny substance resembling that of the 
epidermis (287). In its origin it is tubular, the inner 
part being occupied by the pulp ; but the pulp ex- 
tends only to that portion of the hair which is in a 
state of growth, and never rises above the surface of 
the skin. As the shaft is prolonged from the surface, 
therefore, its cavity is either gradually obliterated, or 
is filled with a dry pith or spongy substance, which is 
supposed to contain air. 

421. The health and vigor of the hair depends en. 
tirely on the health and vigor of the root ; and this, 
as a living organ, is a constituent member of the gene- 
ral system, and its vital interests are inseparably con- 
nected with the general welfare of the body. Every 
injury done to the digestive organs, every instance of 
gluttony or intemperance, or sensual excess of any 
kind, and every violent excitement or emotion of th*e 
mind, such as anger, fear, grief, etc., immediately and 
powerfully affect the roots of the hair, and through 
them the health of the hair itself. Violent grief has 
covered many a head with gray hairs, in a very short 
time ; and violent paroxysms of fear have produced 
the same effect in a few hours : and so has excessive 
sensuality. But the abuses of the stomach, or dietetic 
errors, are probably the most general causes of the 
unhealthiness of the hair, and of baldness, in civic 
life. When the health of the roots of the hair beg^ins 
to decline, the bulb diminishes in size, the Vessels 
lose their power of supplying nourishment, the color- 
ing matter ceases to be deposited, and the hair soon 
becomes gray or white. The hair, therefore, though 
its stem or shaft above the surface of the skin is des- 
titute of vessels and nerves, and has no sensibility, 
ought nevertheless to be regarded and treated as a 
living part of the living body ; and its health should 
be cherished, and its disease avoided or remedied, 
only upon principles and by means which are in per- 
feet accordance with the general laws of life and 
health, and favorable to the well-being of the whole 
system. All external applications, except in so far as 
they contribute to the health and vigor of the roots 
by the cleanliness and exercise of the skin, are en- 
tirely useless, and in most cases decidedly injurious. 
In a healthy state of the hair and its appropriate 
organs it is always supplied with an oily secretion or 
huitus, with which it is anointed ; and it can never 
be benefited, but is generally injured, by the applica- 
tion of any other unction. A proper regard to all the 
physiological laws of the body is the only genuine 
prophylactic for the hair, and the only ground on 
which any one can reasonably hope to restore the 
natural covering to a bald head. 


422. The nails, like the hair, though composed of 
an insensible horny substance, destitute of nerves and 
vessels, have their appropriate organs or roots, by 
which they are produced and sustained, and by which 
also they are physiologically associated with all the 
living organs and parts of the body, and brought 
under their common laws of life and health. They 
do not however appear to sympathize so directly and 
powerfully in the particular affections of the body 
and mind as the hair ; but they are always involved 
in the general and permanent physiological conditions 
of the system ; being more or less moist and pliable, 
or dry and brittle, according to the general state of 

health ; and in some instances they are entirely de- 
stroyed by a general disease of the body, or what is 
probably more correct, by the medicinal substances 
employed to cure the disease. 

423. The truth is, that every part of the living 
body, even the cuticle or epidermis (287), is either a 
living substance, or so closely connected with living 
organs, and so immediately dependent on vital func- 
tions and conditions, that it is brought under the 
general laws of the vital domain, and kept in its best 
condition by the health and integrity of all the organs 
of the system ; and therefore ought always to be 
treated with reference to health and disease, as a con- 
stituent portion of the living body, which cannot be 
either benefited or injured without in some measure 
correspondently affecting the whole vital economy. 


Exercise of the yoluntary powers in procuring food — Mastication 
and deglutition—Gastric digestion— Beaumont's experiments — 
Saliva and gastric Juice, solvent fluids— True chymification only 
effected by the living organs — Fwiction of the pylorus — Import- 
ance of the stomach — Character of the chyme — Indigestible sub- 
stances, how disposed of by the stomach — Not all the properties 
of the food digested—Time employed in digestion — How fluids 
are disposed of— Absorption, by what vessels performed— Fluids 
rarely descend into the small intestine, unless strongly offtensive 
to the absorbents, etc., as alcoholic liquors when first used, etc. — 
Function of digestion, on what its integrity depends — Chyme, 
how presented to the lacteals — Chyle, where formed and by what 
vessels— None in the alimentary cavity — Use of the pancreatic 
fluid — Use of the bile, and ftinctional character of the liver — 
Portal system— Commimication betweeu the liver, kidneys, lungs, 
skin, etc. — Alcoholic liquors, why not at first admitted into &e 
general circulation — Foreign substances found in the portal 
blood — Use of the spleen— Oily matter and acids in the food 
require bile — Chyle secreted — its nature — Process of chylificatioa 
mysterious — Chyle the same whatever the food — Function of the 
mesenteric glands — Globules of the chyle invested with tunics- 
Passage of the chyle to the lungs- Function of respiration — ^Blood 
circulated for the nourishment of the body— Quantity of blood in 
the body, frequency of pulse, etc.— Vitality of the blood, diar- 
acter of its globules, etc. — Saline property of the serum — ^Foreign 
properties in the blood — Animal heat — Nutrition — Secretion — 
Adipose matter, its use — Size of the body determinate — Deoosn- 
position^Depuration — Wear, expenditure, and disease. 

424. Having taken a general survey of the mater. 
ials and construction of the human body, and attended 
to the minuteanatomy of its several organs, as fully as 
is necessary in order to a clear and correct understand- 
ing of the physiology of the system, we are prepared 
to enter upon the more interesting and pleasing study 
of vital function, or the offices performed by the several 
parts of the body as living organs in the wonderful 
economy of the vital domain. 

435. Let us then contemplate the living human 
being, rising from the Creator's hand, and awakening 
to the consciousness of his existence and of his wants, 
and to a perception of the external world. He soon 
feels that special sensation which we call hanger, or 
the instinctive desire for food. This sensation physi- 
ologists have attempted to explain in various ways, 
and most of them with much more fancy than truth. 
My own views in regard to it will be presented when 
I come to speak of the proper times of eating. Promp- 
ted by this instinctive impulse, man exercises his 
voluntary powers for the supply of the want. He. 
looks abroad, and beholds the fruit hanging upon the 
drooping bough of the tree, and by a voluntary con- 
trol of his lower limbs he moves forward to the object 
of his vision. The specific odor of the fruit freighting 
the air which he breathes, is brought into contact wiw. 
his olfactory nerves (399), and he instinctively pef- 
ceives by the special sense of smell, that it is good for 
food. By a voluntary control of his upper limbs, or 
organs of prehension, he puts forth his hand and 
seizes the fruit, and places it between his teeth, with 
which, by a voluntary exercise of the various appro- 
priate muscles attached to his under jaw, he cuts and 



mashes it into minute particles. The instant this 
process is commenced, the special sense of taste (397) 
perceives another specific quality of the food, and cor. 
rohorates the testimony of the sense of smell. And 
while the process of mastication is going on, the mu. 
•cous membrane of the mouth secretes its glairy and 
lubricating fluid (333,339), to shield its delicate little 
.organs (287) from too rude a touch, and to facilitate 
the movements of the food upon its surface, and its 
-passage into the stomach. At the same time, also, 
the salivary glands (340) secrete from the arterial 
blood, and pour into the oral cavity, a copious supply 
of a bland tasteless fluid called the saliva, to be tho- 
roughly mixed with the aliment by the action of the 


426. The functions of the oral cavity are generally 
regarded as merely preparatory for deglutition or swal- 
lowing, and the salivary fluid is considered as simply 
intended for this purpose. But this is incorrect. The 
mucous secretions and serous exhalations of the mouth 
and fauces and oesophagus (339) are abundantly suf- 
ficient for all the purposes of lubrication and dilution 
necessary to prepare the food for deglutition. The 
saliva is truly a solvent fluid, and designed to act as 
such upon the alimentary contents of the oral cavity; 
and always, when the function of mastication is pro- 
perly and thoroughly performed, the process of assim- 
ilation or digestion commences in the mouth; the 
diange effected there being greater or less according 
to the perfectness of mastication, the length of time the 
food is detained in the mouth, and the healthiness and 
purity of the salivary fluid. And it is certain that 
the change can be carried so far as to afford nutrient 
matter to the lymphatics (385, 387) of the parts. By 
hasty and imperfect mastication, therefore, a fourfold 
injury is done to the stomach. 1. It compels that 
organ to receive the food more rapidly than is consis- 
tent with the welfare of its own physiological economy 
(429). 2. It compels the stomach to secrete a larger 
quantity of solvent fluid than would be necessary if 
the functions of the mouth had been properly perform- 
ed. 3. It compels the stomach, at great inconvenience, 
to reduce by maceration those masses which ought to 
have been broken down and finely comminuted by the 
teeth : and 4 ; by increasing the duration and diffi- 
calty of gastric digestion, it increases the expenditure 
of the fiinctional powers of the stomach, and thus 
causes a greater degree of vital exhaustion in that or- 
gan, tending to debility and disease. 

427* When the food is prepared for deglutition, it is 
fathered back upon the arch of the tons^e, whence it 
18 suddenly launched into the pharynx (338, 340), and 
passes into the oesophagus or meatpipe, by which it is 
conveyed into the stomach. In its transition from 
the arch of the tongue to the meatpipe, the food, it 
will be remembered, passes by several orifices, and 
•directly over the mouth of the windpipe. (340). But 
it must not be permitted to enter any of these orifices, 
nor cause any considerable interruption to respiration ; 
•and, therefore, the orifices are closed during its tran- 
sition, and its passage is very rapid ; and hence, the 
function of deglutition or swallowing is somewhat 
»compllcated, and requires the perfect co-operation of 
all we parts concerned. At the instant the food is 
•launched from the arch of the tongue, the muscles of 
'the pharynx (347) contract, shortening that organ, and 
rising up the lar^x (356) ; at the same instant the 
veil of the palate is pressed back, and closes the nasal 
canals and the tubes coming from the ears (340); 
-the epiglottis (340, 354) shuts down and closes the 
l^lottis, or mouth of the windpipe, and the pharynx 
darts up, as it were, and seizes the descending mass, 
And suddenly dropping down, presses it into the meat- 
pipe. If in this process there is any want of consent, 
.or co-operation of the parts ; if the food or drink is 

accidently thrown into the pharynx, without the de- 
terminate action of the will, or if the will attempts 
to arrest the action of swallowing when the food has 
passed a little too far to be recovered; or if there hap- 
pens to be a spasm or paralysis of any of the parts at 
the moment, a derangement of the function takes 
place, and a portion oi the food or drink passes into 
the exceedingly sensitive'mouth of the windpipe (247), 
which instantly gives alarm to its presiding centre 
(219), and a convulsive expulsion of air from the lungs 
drives the intruding substance violently back through 
the mouth and nose, and in some instances through 
the ears. But the irritation produced in the mouth 
of the windpipe does not immediately cease when the 
irritating substance is expelled, and hence an unpleas- 
ant sensation, and perhaps violent coughing, contin- 
ues for some seconds, or even minutes, after the expul- 
sion takes place. 

428. As soon as the cesophagus receives the food, 
its muscular coat (338, 347) contracts upon it from 
above downward, and presses it onward into the stom- 
ach ; and at the same time the mucous follicles (333) 
situated in this narrow passage, pour out their lubri- 
cating fluid, to shield the nerves and vessels of the 
lining membrane (287), and to facilitate the move- 
ment of the descending mass. The cesophagus does 
not cease to act, however, when the food has passed 
from it into the stomach, but continues, and especially 
its lower portion, to contract vigorously from above, 
downward, to the cardiac orifice (341), to prevent a 
regurgitation of the food during the action of the stom- 


429. When the food reaches the stomach, it is in- 
stantly perceived by the delicate \\tt\e feelers (230, 287, 
290) which largely abound in the vasculo-nervous 
web of the mucous membrane, lining the gastric cav- 
ity, and these at once infortn the presiding centre 
(220), which throws its stimulus on the several tissues 
of the organ (313); the muscular fibres (347) are 
called into a rapid and vigorous action ; an increased 
quantity of arterial blood is injected into the vessels 
(393); the nervous power (164) is exalted, and the 
temperature is somewhat elevated. By the contrac- 
tion of the different layers of muscular fibres, the 
whole stomach is thrown into a gentle commotion, by 
which the food is carried around the gastric cavity, 
and everywhere pressed against the internal surface. 
This excites the little vessels, or, as some say, glands 
(332) that secrete a thin transparent fluid, which 
very soon begins, like sensible perspiration, to exude 
from the mucous membrane, in small drops, and min- 
gle with the food. This fluid is called the gastric 
juice ; from gaster, the ancient Greek name of the 
stomach. After the first portion of food has been car- 
ried about the gastric cavity, and freely mixed with 
this fluid, if the stomach be not crowded and embar- 
rassed by a too rapid ingestion or swallowing, its 
muscles relax in some degree, and the organ is prepa- 
red for another portion, which, when received, un- 
dergoes the same process as the first. These opera- 
tions are continued, till the stomach is distended with 
food, and the meal is finished ; when the muscular 
action becomes less rapid, and a gentle, undulating, 
or vermicular motion succeeds, and is kept up, tiU the 
function of the stomach is completed, and its contents 
are emptied into the small intestine. 

430. The process of digestion was formerly supposed 
not to commence till some time after the food is re- ' 
ceived into the stomach ; but this notion is now known 
to be incorrect. When the functions of the oral cav- 
ity are thoroughly performed, the process commences 
th'ere (426). The passage of the food from the mouth 
to the stomach is too rapid to admit of any assimila- 
ting change during the transition. But no sooner is 
the properly masticated food introduced into the 



stomach, than the process of gastric digestion com- 

431. Concerning the nature of this process, and the 
means by which it is effected, the haman mind has 
been busy with its speculations from the time of 
Hippocrates to the present, and perhaps from a much 
earlier period ; and, until a comparatively recent date, 
the results were little more than fanciful and erro- 
neous theories. Some supposed it to be a process of 
putrifaction, others a process of concoction, others of 
fermentation, and others of trituration. Indeed, a 
century has scarcely elapsed since any thing like a 
correct notion began to be entertained on the sub- 
ject; and even yet there is no little discrepancy of 
opinion in relation to it among physiologists. Dr. 
Beaumont, of the United States Army, from his pecu- 
liar advantages, and by his patient perseverance in 
experiments and observations, has perhaps done more 
than any other man to settle the disputed points; 
but even he has evidently been misled in some re- 
spects by false theories, aiid has left broad ground for 

It is, however, well ascertained, that the gastric 
juice is the principal agent under vital control of 
the change which the food undergoes in the ^mach. 
This fluid, as well as that secreted by the salivary 

f lands and the pancreas, has frequently been analyzed 
y the chemists^ but without the most remote advan- 
tage to physiology or medicine. As a matter of chem- 
ical science, we know what substances are obtained by 
a chemical analysis of the fluid taken from the stom- 
ach ; but not the least ray of light is thereby thrown 
upon the physiology of the stomach. We know no 
better than we did before it was analyzed, what are 
the peculiar properties of this fluid in the living stom- 
ach, b^ which it produces its specific effects as an 
agent m the vital process of digestion ; and should we 
attempt to assist the stomach by throwing into it any 
of those substances which result from a chemical ana- 
lysis of the gastric juice, we should be more likely to 
injure than to benefit the organ. Indeed, it is well 
known that both thechemical and physiological char- 
acter of the gastric juice is very considerably affected 
by the dietetic habits, by the general state of the 
health, by the affections o^ the mind, and by the con- 
ditions of the stomach ; and this is also true of the 
salivary and pancreatic fluids, and in fact of all the 
fluids of the body. All physiological and medical and 
dietetic theories and practices, therefore, founded on 
chemical knowledge in regard to the secretions and 
assimilating changes which are produced by the or- 
ganic economy, are established in utter darkness, and 
are more frequently the source of evil than of good to 

432. We are told, it is true, that the gastric juice 
can be taken from the living stomach, and put upon 
cooked and masticated food in a glass vessel, and that 
if it be kept at the temperature of the stomach (434), 
it will, in the course of several hours, digest the food; 
and some of tho chemical physiologists assert that they 

* Dr. Beaumont published, in the close of the year 18SS, his 
' Experiments and Observations on the Gastric Juice and the Phy- 
siology of Digestion.' These experiments * weie commenced in 
l&iS, and continued, with various interruptions, till 1833.' The 
tul^ect of them was Alexis St. Martin, a Canadian of French des- 
cent, who, in 1822, when about eighteen years ef age, with a good 
constitution and robust i\ealth, was accidentally woimded by the 
cUadiarge of a musket, the contents of which were received in his 
left side, and carried away the parts, so asto woundthelungsandsto- 
mach very seriously. Under the eare of Dr. Beaumont, St. Martin 
recovered his health; but in the healing of the parts, the lacerated 
coats of the stomach attached themselves to thelipc of the exter- 
nal wound, and fbnned an artificial aperture to the stomach ; so 
that the gastric cavity could be examined, and substances put 
iato or taken (ham it at any time, by pushing in a valve which 
the stomach had formed to dose the aMrture, so as to prevent its 
contents ftam escaping thereat. Dr. Beaumont's advantage* for 
gastric experiments and obeervatioas were therefore probably bet- 
ter than have ever be«i enjoyed by any other man, and they ware 
diligently and fkithftiUy improved. 

can prepare an artificial gastric juice which will do 
the same. And without doubt they can prepare an. 
artificial gastric juice which will digest tie food as 
well as will the fluid taken from the stomach. But 
the truth is, that neither the artificial nor real gastric 
juice can effect the changes in an inorganic vase, 
which are produced in the fiving stomach. They may 
macerate or dissolve the substances on which they act, 
and reduce them to the consistency and appearance of 
the digested contents of the stomach, but they can- 
not produce genuine chyme, from which the appro- 
priate organs of the living body can elaborate chyle. 

433. The gastric fluid, therefore, is, in truth, a vital 
solvent; for although it undoubtedly possesses, in some 
degree, from its intrinsic character, a solvent and an 
antiseptic power, especially if it be kept at a high tem- 
perature, yet it is only when acting under the vital 
control of the living organ that it can be in any mea- 
sure the agent of that vital change which is essential 
to genuine chymification ; and even in the living 
stomach, when the process of digestion is healthfully 
going on, if by any means the nervous power of that 
organ be considerably diminished (164), the process 
will be retarded, and perhaps wholly arrested, and 
inorganic afiinities will become active, and inorganic 
combinations result, in direct hostility to the vital 
welfare. For not only disintegration and decomposi- 
tion, but new and peculiar combinations take place in 
the vital changes, which are effected by the digestive 
organs ; and these combinations, as we have seen 
(117), are the results of afiinities or forces which act 
in opposition to the inorganic affinities of matter ; and 
the inorganic affinities are subdued, and the vital affin- 
ities superinduced, only by the immediate and control- 
ling influence of the living organ (121). 

434. During the early stages of gastric digestion, 
the pyloric orifice of the stomach (341) is completely 
closed by the contraction of the muscular fibres of the 
pylorus (347), so that the contents ofthe gastric cavity 
cannot be pressed into the small intestine by the mus- 
cular action of the stomach, and the alimentary mass 
is kept in constant motion, and becomes thoroughly 
permeated by the gastric juice. The temperature of 
the stomach is somewhat elevated by the concentration 
of vital power in the tissues of the organ, to enable it 
to perform its function. In a healthy and vigorous 
body, it varies from a hundred to a hundred and four 
degrees Fahrenh. When the digestive organs have 
been impaired, and chronic debility and preternatural 
irritability induced in them, this concentration of 
vital energy during the process of digestion is often 
attended with a disagreeable feeling of chilliness of 
the external surface of the body, and many of the 
symptoms of an internal fever, and more especially if 
the dietetic habits are objectionable. 

435. By the solvent power oi the gastric juice, the 
food is gradually reduced to a soft pultaceous mass, and 
brought into a proximate state of chymification. The 
portions of the mass which come in contact with the 
mucous membrane ofthe stomach are then still further 
acted on by the vital powers ofthe organ, and, in a 
peculiar and inexplicable manner, the nutritious pro. 
pertiesof the aliment are converted into a substance 
very different from anything in the food when it was 
received into the stomach. This substance is real 
chyme ; and in the language of physiology, it is said 
to be homogeneous ; and so far as chemical tests can 
determine, it is nearly identical in character, whatever 
be the kind or kinds of food from which it is formed. 
But in regard to its physiological qualities, and its 
nice relations to the vital economy, its character varies 
with the food, as we shall see hereafter (456). 

436. When the portion of aliment which comes in 
contact with the mucous membrane of the stomach is 
converted into chyme, it is carried forward by the 
muscular action of the stomach, slowlv, towards the 
small extrenuty, and, as it advances, the chymifying 



ehangfe is more and more perfected, till it reaches the 
pylorus or gate-keeper (347), which, by a nice organic 
instinct, perceives its character and condition, and 
immediately opens and suffers it to pass into the por- 
tion of the small intestine called the duodenum (338). 
When the pylorus is in a perfectly healthy state, if a 
crude mass of undigested food attempts to pass into 
the duodenum with the chyme, it instantly closes, and 
the intruder is carried back, to be subjected still fur- 
ther to the operations of the stomach. If it be of an 
indigestible nature, it is finally either permitted to 
pass into the intestinal tube, or is suddenly and con- 
vulsively ejected from the stomach, through the meat- 
pipe and mouth« But when the stomach is greatly 
debilitated, and its organic sensibilities become unheal- 
thy (296), the integrity of the pylorus is impaired, and 
crude substances are frequently permitted to pass into 
the intestines, where they become the causes of irrita- 
tion, and produce many uncomfortable disturbances, 
and in some instances fatal disorders. 

437. When one portion of the contents of the gas- 
tric cavity is chymified and removed into the duode- 
num, another portion comes in contact with the inner 
surface of the stomach, and is operated on in the same 
manner, till the whole mass is chymified and carried 
into the small intestine. But if, by a paralysis of the 
muscles of the stomach, or any other means, the chy- 
mified portion in contact with the inner surface of the 
org^n is not removed, the process of chymification is 
entirely arrested. It is therefore essential to genuine 
chymification, that every portion of the alimentary 
matter should come in contact with the living organ ; 
and in order to this, each successive portion, as it is 
chymified, must be removed ; and hence muscular 
action, though not immediately concerned in the vital 
change which takes place in the portion of the food 
in contact with the mucous membrane, is nevertheless 
as essential to the general function of the stomach as 
nervous power. 

438. Not only the unlearned reader, but even physi- 
ologists themselves, are often betrayed into error by 
the indefiniteness of the language used in physiologi- 
cal works. When it is said that the alimentary matter 
received into the stomach is, by the process of diges- 
tion, converted into a homogeneous substance called 
chyme, it should be understood that this is a general 
statement, which in fact is not strictly true. All the 
alimentary substances in nature suitable for human 
food, consist of certain proportions of nutritious and 
innutritions matter, and the anmentary organs of man 
are constituted to receive and act upon such substan- 
ces. In the process of digestion, therefore, it is only 
the nutritious portion of the alimentary matter on 
which we subsist that undergoes the assimilating 
change, and is converted into real chyme. The innu- 
tritious portion is simply separated from the nutritious, 
and reduced to such a state and condition as fit it to 
pass along the alimentary tube as fecal or excremen- 
titious matter. Nor is it strictly true that all the 
nutritious properties of our food are perfectly chymi- 
fied in the stomach, as is generally supposed. This 
error has grown out of the notion that the stomach 
is peculiarly and exclusively the organ of chymifica- 
tion ; but this process, as we have seen (320), is com- 
mon to the whole alimentary cavity. The stomach 
receives the food from the mouth, more or less chang- 
ed, according as the functions of the oral cavity have 
been more or less perfectly performed C426). In the 
gastric cavity, a general solution of the alimentary 
matter is effected, and, in the nutritious portion, the 
assimilating change is very far advanced ; and, in some 
parts of it, the process of chymification is perfected, 
and the matter is prepared for the action of the organs 
which elaborate the chyle; and undoubtedly this 
matter is acted on to some extent by those organs, 
before it leaves the stomach (388). In other portions 
of the nutritious matter the chymifying change is not 

perfected in the gastric cavity, and therefore the pro- 
cess remains to be completed in other sections of the 
alimentary canal. 

439. Some kinds of food pass through the stomach 
much more slowly than other kinds ; and the stomach 
of one individual differs from that of another, in re- 
gard to the time employed in the process of digestion ; 
and even the same stomach varies in this respect very 
considerably with the varying circumstances and con. 
ditions of the individual ; but as a general statement, 
the food received at an ordinary meal undergoes the 
process of gastric digestion, and passes from the stom- 
ach into the duodenum, in from two to five hours. 

440. When water is received into the stomach, it 
does not appear to undergo any change in the gastric 
cavity, but is all removed by absorption in a very few 
minutes, if the stomach is healthy and vigorous, and 
still more rapidly in some forms of disease, when the 
mucous membrane of the stomach (338) is inflamed, 
and the system is laboring under general symptoms 
of fever, attended with great thirst. In chronic dis- 
eases of a dyspeptic character, on the other hand, ab- 
sorption often takes place very slowly, and the water 
which is drank will sometimes remain in the gastric 
cavity for hours, retarding digestion, and causing^ 
acidity, flatulence, and eructations ; and finally, per- 
haps, the greater part of it will be regurgitated or 
thrown up, with portions of undigested food. When 
liquid food, or water holding in solution any kind of 
nutritious animal or vegetable matter, such as flesh or 
vegetable brotb or soup, is taken into the stomach, 
the aqueous part is all absorbed before the process of 
digestion commences. Milk also is managed in a simi- 
lar manner. The gastric juice separates the curd 
from the aqueous portion, and the latter is absorbed, 
and the curd is then digested. But when indigestable 
substances are received into the stomach in aqueous 
solution, they are absorbed with the water, and pass 
into the vital domain with no apparent change. 


441. In what manner, and by what particular 
agents, this absorption of unchanged matter is effected, 
are questions about which there has been a vast 
amount of controversy ; to settle which, very numer- 
ous and diversified experiments have been made on 
living animals and dead substances, and with very 
different and inconclusive results. We have seen that 
the skin and mucous membrane constitute the great 
enveloping and limiting membrane of the vital do- 
main (288, 330), through which every thing passes 
that enters into or egresses from that domain, and 
that there is on every part of the exterior surface of 
this limiting membrane a vasculo-nervous web or 
plexus formed by the minute extremities of arteries, 
veins, lymphatics, and nerves (287). Of these three 
kinds of vessels entering into this web, the veins 
appear to be much the most numerous, and especially 
in the alimentary canal, where, according to Dr. 
Horner, who is probably correct, the venous capilla- 
ries of themselves form a superficial plexus (380, Note). 
Now the grand question is, whether the lymphatics 
absorb both assimilated and unassimilated substances ? 
or whether they absorb only assimilated, and the veins 
only unassimilated substances ? Some physiologists 
have embraced one of these views, and some the other ; 
and both have perhaps been equally confirmed^ by ex- 
periments on living animals. These experiments, 
however, have been wholly inconclusive, and from the 
nature of things, they ever must be. The actions of 
any part of the living body under the anguish and 
agonies of such experiments, cannot afford conclusive 
evidence of the normal and regular functions of those 
parts (216). Undoubtedly, under such circumstances, 
both the venous capillaries and the Ivmphatics can be 
made to absorb foreign and unassimilated substances ; 
and the fact settles no principle in physiology. The 



question is not, what are the abnormal possibilities of 
the organic system ? but what are the regular and 
appropriate functions of the parts in the normal con- 
dition and operations of the vital economy ? Here 
there seems to be less ground for dispute ; for there is 
little reason to doubt that, in the regular and undis- 
turbed performance of their appropriate functions, 
the lymphatics, including the lacteals (387), are prin. 
cipaliy confined to assimilated and assimilable sub- 
stances ; and foreign and unassimilated substances 
are mostly absorbed by the venous capillaries. It is, 
however, probable that in some instances foreign sub- 
stances find their way into the lymphatic extremities 
which inosculate with the venous capillaries, and 
which transfer those substances to the veins in the 
lymphatic glands, in the portal system, and at other 
points of connexion (386). 

442. The venous capillaries, then, which form the 
superficial venous plexus of the mucous membrane of 
the stomach and intestines (380), are undoubtedly the 
vessels which absorb the water and other substances 
that pass unchanged from the alimentary cavity into 
the vital domain ; and these capillaries we know to be 
the radicles of the great venous trunk of the portal 

■^system (381), through which, as a general fact, all 
unassimilated substances that enter the general cir- 
culation, find their way to the vena cava (378). 

443. The pyloric orifice of the stomach being nearly 
on a level with the cardiac orifice (341), or that at 
which the food enters (fig. 23, c 6), the contents of 
the gastric cavity do not descend into the intestines 
by the force of gravity, but are, as it were, lifted up 
and pressed through the pyloric orifice by the con- 
traction of the muscular fibres of the stomach (347). 
But there is comparatively little of this action when 
pure "water is received into' the gastric cavity, and con- 
sequently very little of this fluid ordinarily passes 
into the small intestine, but is mostly taken up by the 
absorbents of the stomach. When irritating and 
deleterious substances are mingled with the water, 
however, the absorbents of the stomach receive it 
much more reluctantly; and, as the stomach will 
not long retain it, a considerable portion of it is ex- 
pelled from the gastric cavity into the small intestine. 
Hence, when ardent spirit is introduced Into the 
stomach of animals, and they are shortly after killed 
and examined, the mucous membrane, not only of the 
stomach but also of the small intestine, is always 
found highly inflamed. 

444. The healthfulness and integrity of the diges- 
tive function of the stomach, then, depend principally 
on three things : — 1, healthy and vigorous nervous 

Sower (164); 2, healthy secretion (429); and 3, 
ealthy and vigorous muscular action (347) ; and nei- 
ther of these can be impaired without injuring the 
others. The nervous power always suffers from all 
inordinate mental action and excitement, and especi- 
ally from the depressing passions, such as fear, grief, 
painful anxiety, etc. (304). Narcotic substances, of 
every kind, and in fact all purely stimulating substan- 
ces, also impair the nervous power. Improper kinds 
and conditions of food, gluttony, lewdness, sensuality 
of every kind, in short every thing that tends to 
impair the general health of the body, serves to dimin- 
ish the nervous power of the stomach ; and all these 
causes injuriously affect the secretions and the mus- 
cular power and action of that organ, and consequently 
impair the healthfulness and integrity of its func- 


445. As the chyme passes from the gastric cavity 
into the duodenum, or upper portion of the small in- 
testine (338), it is instantly perceived by the innu- 
merable little feelers or nerves of organic sensibility, 
in the vasculo-nervous plexus of the mucous membrane 
(287^ 290), and they, like those of the stomach (429), 

immediately inform their presiding centre or centres 
(220), by which the muscles of the part are excited to 
action, causing a vermicular or worm-like motion, by 
the successive contraction of the fibres (347) from 
above downwards. By this motion the chyme is 
slowly carried along the intestinal tube, its course 
being considerably retarded by the semilunar folds 
of the mucous membrane (346, fig. 29) ; and at the 
same time a solvent fluid, nearly resembling the gastric 
juice, exudes from the vessels of the membrane (339). 

446. As soon as the chyme enters the small intes- 
tine, the lacteals, which, as we have seen (388), very 
numerously abound in this section of the alimentary 
canal, begin to act on the most perfectly assimilated 
portion of it, and to elaborate from it their peculiar 
fluid, called the chyle ( 153;. And as the chyme moves 
slowly along the living tube, presenting its most per- 
fectly assimilated portions to the lacteals of the suc- 
cessive parts, the digestive or chymifying process is 
at the same time carried on by the vital energies and 
secretions of the tube ; so that, while the lacteals in 
one part of the intestine are acting on the most per- 
fectly assimilated portion of the chyme, the less per- 
fectly assimilated portions are preparing for the lac- 
teals' of the succeeding part. In this manner the two 
assimilating processes are carried on through the 
whole length of the small intestine, or until all or 
nearly all of the nutritious matter of the food is conver- 
ted into chyme and chyle. Some physiologists suppose 
these processes are continued in the large intestine, 
and that the coecum (346) acts as a kind of second 
stomach, to complete the digestion of the nutritious 
matter which may be received from the small intes- 
tine ; and it is undoubtedly true that nutrition may, 
to some extent, be effected through the large intestine 
(388), and that, when nutritious matter reaches this 
section of the alimentary canal, both chymification 
and chylification to some extent take place in it. 
The principal office of the large intestine, however, 
is to receive and dispose of the fecal or excrementi- 
tious matter of the food. But whether the process of 
chymification is ordinarily continued into the large 
intestine or not, it is very certain that the most per- 
fect performance of the functions of the small intes- 
tine, including both chymification and chylification, 
requires that the stomach should not be employed at 
the same time ; and hence, the reception of food or 
other substances into the gastric cavity at improper 
times, and in fact all dietetic irregularities, always in 
some measure disturb the functions of the small intes- 

447. It has generally been supposed that the chyle 
is formed in the small intestine, by the mixture of 
the pancreatic juice and bile with the chyme, and that 
it is merely absorbed or sucked up, and conveyed to 
the thoracic duct, by the lacteals (388). This notion, 
however, is entirely erroneous, and will probably soon 
become obsolete. There is not a particle of chyle 
formed in the alimentary cavity. The only assimila- 
ting change effected in that cavity, is, as we have seen 
(320), that of chymification ; and, therefore, all the 
secretions, both of the alimentary canal and of its 
glandular appendages (343) which are in any manner 
immediately concerned in the great process of assim- 
ilation, are employed in the production of chyme. 
The pancreas (S^), in structure and appearancis, is 
almost precisely like the salivary glands, and there is 
no essential difference between the pure salivary, 
gastric, and pancreatic fluids, the different degrees <^ 
acid and other qualities found in one or the other of 
these fluids being wholly accidental, and owing to the 
physiological condition of the system, or to the pecu- 
liar state of particular organs. The pancreatic fluid, 
therefore, is employed in perfecting the process of 
chymification in the small intestine ; and accordingly 
the pancreas, as well as the salivary glands, is propor- 
tionably largest in those animals which subsist on 



food that requires the greatest quantity of solvent fluid 
for its chymification. 

448. In order to a clear and correct understanding 
of the use of the bile in the economy of the alimentary 
cavity, it is necessary that we should take a compre- 
hensive survey of most of the parts contained in the 
abdomen. 1. The alimentary canal presents a surface 
of about thirteen square feet of mucous membrane ; 
and this surface is everywhere covered by a close 
plexus of minute vessels and nerves, which are em- 
ployed in the performance of greatly diversified and 
most important functions (331 ) ; and of these vessels, 
the venous capillaries are by far the most numerous. 
2» All the venous capillaries of this extended surface, 
together with those of the spleen (381), of the pan- 
creas, of the mesenteric glands, etc. (386), run into 
veins, which unite to form the great venous trunk of 
the portal system (381 ) . 3. The portal trunk, instead 
of proceeding to the heart or vena cava (378), plunges 
into the liver (335, 341), where it is ramified in pre- 
cisely the manner of an artery, and holds the same 
relation to the biliary ducts that the artery does to 
the excretory ducts of other glands (334), and forms 
by far the greatest part of the vascular substance of 
the organ ; while the hepatic artery is evidently de- 
signed for the nourishment of the tissues of the liver, 
for it is distributed on other vessels, giving rise there 
to a very complex net-work. The finest ramifications, 
however, enter the vena porta ; and the hepatic veins, 
the twigs of which are fewer and larger than those of 
the vena porta, and the hepatic artery, receive their 
blood, not from the artery, but from the vena porta. 
4. According to the general law of the organic econ- 
omy (393), that as the defi^ree of vital action in a part, 
so is the supply of arterial blood to that part, a great 
quantity of arterial blood is sent to the stomach and 
intestines during the performance of their general 
function of digestion ; and a large proportion of the 
volume of this blood, remaining after the tissues of 
the organs are nourished and their vital powers re- 
plenished (376), and the secretions, exhalations, etc., 
are accomplished, is by these processes converted into 
venous blood, and must be returned to the heart and 
lungs for renovation, d. Not only the water which 
is received into the stomach as drink, but the aqueous 
portions of the food, and many other substances, some 
of which, if permitted to pass intt> the general circu- 
lation, would prove exceedingly deleterious to the sys- 
tem, are absorbed, unchanged, and mingled with the 
venous blood just spoken of ; and hence this blood, 
so freighted with impurities, instead of being permit- 
ted to return to the heart and lungs in the ordinary 
manner of the venous blood from the other parts of 
the body, is furnished with the peculiar apparatus of 
vessels which constitute the portal system (381), and 
by which it is poured into the largest gland, and al- 
most the largest organ of the whole body ; and thus all 
the venous blood from the tissues of the alimentary 
canal, with all its foreign substances and impurities, 
is filtered through the Hver before it reaches the heart, 
and returns to the pulmonary and general circulation ; 
and it is entirely certain that the liver, in its normal 
state, and in the regular performance of its function, 
secretes the bile from the blood thus furnished by the 
portal veins, and not from the arterial blood ; the latter 
being necessary only to nourish the tissues of the or- 
gan, and sustain their functional powers, and supply 
the biliary ducts with mucus : yet, after having don^ 
all this, and become venous blood, it enters with the 
portal blood into the venous plexus where the bile is 
secreted ; and, therefore, in the absence of supplies 
from the vena porta, bile can be secreted, to some ex- 
tent, from the blood which enters the liver into the 
hepatic artery. Again, we know that when foreign 
substances are absorbed from the alimentary canal, if, 
by any means, they can be detected in the blood, they 
are readily found in the spleen, in the portal veins, and in 

the liver, even when no trace of them appears in the 
thoracic duct (386) nor in the general circulation. 
Indeed it is nearly certain that, in the general health 
and perfect integrity of the system, there is a way by 
the intercommunication of the veins and lymphatics 
(386), through which foreign and unassimilated sub- 
stances, absorbed from the alimentary cavity, are car- 
ried off to the kidneys, lungs, skin, and other organs, 
and expelled from the vital domain, without being 
permitted to enter into the general circulation. But 
when deleterious substances are habitually received 
into the alimentary cavity, and taken up by the ab- 
sorbents, the nicely discriminating organic sensibility 
of the organs (296) is gradually depraved, and their 
function^ integrity impaired, till they finally suffer 
those substances to pass freely into the general circu- 
lation, and throughout the whole system. And hence 
it is that when ardent spirit is only occasionally 
drunk, it can very rarely, if ever, be detected in the 
general circulation, even while it is strongly exhaled 
from the lungs ; but when an individual becomes an 
habitual drunkard, and continues his inebriation for 
several days in succession, the blood taken from the 
vein of tne arm is found strongly charged with 

449. Still further, in regard to the liver and its 
secretion, it is now well ascertained that the bile is 
not in any manner directly concerned in the forma- 
tion of cnyle, nor is it indirectly subservient to that 
end, any further than it may assist in the process of 
solution, preparatory to chymification ; for both chyme 
and chyle are regularly produced without any agency 
of the bile (388). Moreover, itis^ell known that 
the liver is largely developed, and performs its secre- 
tory function to some extent, before chymification 
and chylification take place in the system. Besides, 
if the hver had been designed to secrete a fluid essen- 
tial to the assimilating processes of the alimentary 
cavity, and primarily intended for that use, it would 
be furnished with no sac or reservoir to receive and 
retain its secretion, but would, like the salivary 
glands, secrete its fluid only when the wants of the 
vital economy required it, and pour it directly into 
the cavity, where it was needed. But the secretion 
of the liver is continually going on ; and because the 
bile cannot be continually poured into the alimentary 
cavity, consistently with the general and particular 
regulations of the vital economy, the liver is furnished 
with a reservoir (341), which receives its secretion, 
and retains it until an opportunity is afforded for its 
discharge into the alimentary cavity. 

450. Now, then, in view of all these facts, is it not 
fully evident that the liver is a great filtering gland, 
designed to separate the impurities from the venous 
blooMd of the portal system coming from the tissues of 
the alimentary canal ? But we have seen that there 
is a large quantity of this blood, and that the whole 
of it must filtrate, as it were, through the liver (448), 
before it reaches the heart; and furthermore, the 
quantity of blood in the portal system is not always 
the same. The arterial supply to the alimentary 
organs being greatly increased during their perform- 
ance of the function of digestion (393), there is con- 
sequently, and somewhat suddenly, a commensurate 
increase of the quantity of venous blood returning 
from those organs. At the same time, also, consider- 
able quantities of aqueous fluid are, or may be, ab- 
sorbed from the alimentary cavity (440^, and mingled 
with this blood in the portal veins, greatly and sud- 
denly increasing its volume. It follows, therefore, 
of necessity, eiuier that this heterogenous fluid is at 
times driven through the liver with excessive rapidity, 
or that the veins of the portal system are at times 
suddenly and excessively distended, or that there is 
connected with the portal system a vascular appen- 
dage, which serves as a reservoir to receive a portion 
of this fluid, when its volume is increased, and retain 



it till the liver, in the regular performance of its func- 
tion, is prepared to act upon it. Precisely such a vas- 
cular appendage is found in the spleek (382). The 
structure of that organ, its connexion with the portal 
system, the regular increase of its volume with the in- 
crease of venous hlood returning from the tissues of the 
alimentary canal, its somewhat sudden enlargement 
when fluids are absorbed from the stomach, and the 
fact that foreign substances absorbed from the stom- 
ach are invariably to be found in its blood, if they 
are such as can be detected at all within the vital 
domain ; and the fact also that it can be extirpated 
from the bod^ without destroying life, and apparently 
without detriment to health, all concur to prove most 
conclusively, that the spleen is nothing more nor less 
than such an appendage or reservoir to the portal 
system. And the whole organization, arrangement, 
and economy of the parts, clearly prove that the 
portal system, the spleen, and the liver, constitute an 
apparatus of organs designed to receive the venous 
blood from the tissues of the alimentary canal, min- 
gled with whatever foreign substances may be absor- 
bed from the alimentary cavity, and so far to purify 
that blood, as to prepare it to return to the heart and 
lungs, with safety to the vital domain. And this 
purification evidently does not consist exclusively in 
the secretion of bile, but it is nearly certain that this 
apparatus has a vascular communication with the 
kidneys and lungs, and perhaps also with other or- 
gans, through which it disposes of foreign and unassi- 
milated substances without sufl^ering them to pass 
into the general circulation (448). 

451. The grand function of the liver, in the vital 
economy of the general system, therefore, is evidently 
that of a depurating or cleansing organ ; and conse- 
quently the bile is primarily an excrementitious sub- 
stance, thrown into the alimentary cavity, to be car- 
ried off with the fecal matter of the food ; and hence, 
as a normal fact, it enters freely into the small intes- 
tine only when that tube is distended with alimentary 
matter, and then always mixes most intimately with 
the fecal portions of that matter. It is nevertheless 
true, however, that though the bile is secreted for the 
primary purpose of purifying the blood, and is there- 
fore an excrementitious substance, yet by a wise pro- 
vision it is in some respects made subservient to the 
chymifying or digestive process of the alimentary 
cavity. How far our benevolent Creator prospec- 
tively adapted the range of capabilities in this por- 
tion of the organic economy, to the artificial and de- 
praved habits of man, it is impossible to say ; but it is 
certain that those habits do extensively call into re- 
quisition the biliary secretion for purposes which are 
by no means compatible with the best interests of the 

452. Not only the animal, but nearly all the vege- 
table substances on which man subsists, contain more 
or less of fatty or oily matter ; and it is now fully 
ascertained, that when this matter is introduced into 
the alimentary canal, the gastric juice has little or 
no effect on it, until it is in some measure changed by 
other means. When only the lean part of flesh-meat, 
or such vegetable substances as are best adapted to 
the alimentary wants of man, are received into the 
human stomacn, the oily matter is in so small a pro- 
portion, and so diffused in particles through the gene- 
ral mass, that the food is sufficiently digested in the 
gastric cavity to afford portions of perfect chyme for 
the action of the lacteals, and to fit it to enter the 
duodenum, with little or no change in the oily mat- 
ter. Soon after it is received into this section of the 
alimentary canal, the bile is mixed with it (341), and 
acts on the oily matter as an alkali, and converts into 
a saponaceous substance, which is immediately acted 
on by the solvent fluid from the pancreas (447), and 
other chymifying agents of the small intestine (445), 
and with difficulty converted into chyme. But when 


a considerable proportion of the food consists of animal 
or vegetable fat or oil, it cannot be so far chymified 
in the stomach, by the secretions and actions of that 
organ, as to fit it to enter the small intestine safely, 
and without disturbance. In this emergency, the 
stomach is irritated by the presence of the unmanage- 
able substance, and the biliary apparatus sympathiz- 
ing ^2979 ^1) ^i^^ the stomach in its irritations, 
pours the bile freely into the duodenum, where, in- 
stead of descending in the usual manner along the 
alimentary canal (341), it is carried up, and admitted 
through tne pyloric orifice, into the gastric cavity, to 
assist the stomach in the digestion of its contents, by 
i^onverting the oily matter into a kind of soap, and 
thus rendering it soluble by the gastric juice. But 
the introduction of the bile into the stomach, though 
rendered necessary by such exigencies, is neverthe- 
less utterly incompatible with the best physiological 
condition and most perfect functional integrity of that 

453. Besides the oily matter of our aliment, there is 
frequently more acid in some kinds of food than is con- 
sistent with the welfare of the intestines; and this acid 
is, in some measure, neutralized by the alkaline proper- 
ties of the bile, soon after the chyme enters the duo<> 

454. To act as an alkali on the oily matter and the 
acids of the alimentary contents of the intestines, is 
therefore the secondary t and often very important, use 
of the bile, and in no other respect or manner is it 
concerned in the production of chyle. 

455. The chyle, I have said (447), has generally 
been supposed to be formed in the small intestine, and 
to be merely sucked up by the lacteals ; and hence, in 
all works on physiology, these vessels are said to absorb 
the chyle. But as there is not a particle of chyle form- 
ed in the alimentary cavity, the function of the lac- 
teals is rather that of secretion than of absorption ; 
for, instead of simply sucking up a substance already 
formed, they elaborate, as it were, an entirely new 
substance from the most perfectly chymified portions 
of the food ; and in this process, it is evident that 
there is a further decomposition of the chymified mat- 
ter, and new combinations and arrangements of its 
particles, so that the chyle possesses a different con- 
stitutional nature from the chyme, and is essentially 
a different substance (140). Indeed, this is a vital 
function of a mysterious and most wonderful charac- 
ter, which has completely foiled the ingenuity and 
beggared the calculations of the chemical physiologists, 
who, taking the results of the chemical analysis of 
dead animal matter for their data (147), have endea- 
vored to reason out the elementary laws of vital ac^*- 
tion and organic combination. In vain have they at- 
tempted to regulate the diet of man on chemical prin- 
ciples ri51), and insisted on the necessity for certain 
chemical properties in human aliment, to sustain the- 
vital economy. That economy has shown them that 
it can triumph over the chemical affinities and ordinary 
laws of inorganic matter, and bend them to its par- 
poses at pleasure; generating and transmuting from 
one form to another, with utmost ease, the substances 
which human science calls elements (51^ ; and while 
the living organs retain their functional power and 
integrity, elaborating from every kind of aliment on 
which an animal can subsist, a chyle so nearly iden- 
tical in its physical and chemical character, that the 
most accurate analytical chemists can scarcely detect 
the least appreciable difference.* 

* The scientific world has been greatly misled on this subject by 
the inaccuracies of the chemists. We have been told by aome, 
that chyle formed from vegetable food contains much more carbon 
and less nitrogen than that formed firom animal food ; but it is 
now ascertained that all such statements are incorrect, and tiiat 
if there be perfect health and functional integrity of the assimila- 
ting organs and of the system generally, the chyle formed firom 
vegetable and that from animal matter are so nearly identical in 
chemical composition, that no appreciable difference can be detec- 
ted by the most careful and accurate analysis. 



456. The Iftcteals seem to possess the transmuting 
power of vitality in an eminent degree. The chyle 
which is found nearest to the secreting radicals or 
mouths, is of an entirely different nature from the 
chyme in the alimentary cavity (153). It is a thin 
aqueous fluid, of a milky or pearly appearance, and is 
slightly albumenous, and when examined under the 
microscope, is found to contain the globules (157) 
peculiar to animalized matter^ and which are supposed 
to be the elementary nuclpi of all the solid forms of 
matter in the living bo^. The color of this fluid 
varies somewhat with the quality of the aliment, 
being always more white in proportion as fatty or oily 
matter abounds in the food. As the chyle flows along 
the lacteals, and passes through the mesenteric glands 
(386) (figs. 43, and 46, d e), it is more and more as- 
similated to the blood; and, before it mingles with 
this latter fluid, it is apparently like it in all respects, 
excepting color (154). The proportion of its fibrin, 
or more correctly speaking, of its globules, to its other 
properties, even in a carnivorous animal accustomed 
to a mixed diet, is so nearly the same, when the food 
is exclusively vegetable, and when exclusively animal, 
that the difference is scarcely appreciable. But the 
chyle elaborated from purely vegetable food differs in 
one respect, most remarkably, from that formed from 
purely animal food. When taken from its living or- 
gans, the chyle elaborated from animal food putrefies 
in three or four days at longest, while that from the 
vegetable food may be kept for several weeks without 
becoming putrid. This is an exceedingly important 
physiological fact, which does not seem to have been 
sufliciently appreciated by physiologists (914). 

457. In regard to the effect which the mesenteric 
glands have upon the chyle in its passage through them, 
there has been some diversity of opinion among phy- 
siologists ; and yet, when the structure and oflice of 
these glands are contemplated in connexion with the 
general and particular economy of the system, there 
appears to be little ground of doubt concerning them. 
They are, as we have seen (386), little m-ore than in- 
tricate plexuses of minute vessels and nerves, having 
none of the peculiar characteristics of secreting organs, 
and are therefore more properly called vascular gang- 
lions, than glands. The vessels of these ganglions 
consist mostly of lacteals or lymphatics ; and with 
these are associated numerous veins, which arise from 
the ganglions, and which in the ganglions communi- 
cate with the lacteals or lymphatics, by opening the 
one into the other. It can hardly be doubted, there- 
fore, that these ganglions are formed for the sake of 
establishing such communications between the lac- 
teals or lymphatics and the veins, as will enable the 
former to expel into the latter such foreign or other 
substances as they may contain, which cannot safely 
or consistently with the greatest good of the system 
be permitted to pass into the thoracic duct.* The 
chyle, in passing through these ganglions, therefore, 
is probably no further affected than to be in some 
measure purified by the removal of the foreign sub- 
stances or crudities which it may contain. This opin- 
ion appears to be supported, not only by the anatom- 
ical structure of these ganglions and the general phy- 
siological analogies of the vital economy, but also by 
all the physiological phenomena pertaining to them 
both in their healthy and in their morbid state. 

458. If the opinion of some anatomists, that most 
or all the lacteals traverse a portion of the liver (388) 
before they reach the thoracic duct, be correct, it is 
probable that they do so for the purpose of still fur- 
ther communicating with venous capillaries, into 
which they may discharge any remaining crudities or 
unassimilated substances contained in the chyle. 

459. When the chyle reaches the thoracic duct 
(386), into which it is conveyed by the lacteals (fig. 
46, bfg), it is in a very advanced state of assimila- 
tion to the blood, being possessed of a considerable 

share of intrinsic vitality (203), and largely abound- 
ing in elementary animal molecules (456). B^ore 
leaving the thoracic duct, each of these minute ani- 
malized molecules becomes invested or surrounded by 
a thin pellicle or tunic, and being thus invested they 
are prepared to enter into the great highway of the 
returning circulation, and after having undergone the 
process of the lungs, to become the globules of the 
blood. Sometimes also the chyle is found to be slightly 
pink-colored before it leaves the thoracic duct. Being 
in all respects prepared for a passage to the lungs, in 
company with whatever impurities it may meet with 
in the venous blood (448), the chyle is carried up by 
the thoracic duct (fig. 45, d rf), and emptied into the 
subclavian or large vein coming from the left arm, 
at the point and in a manner which I have described 
(386). Here it mingles with the venous blood, with 
which it flows into the right auricle of the heart 
(368, 369), and thence passes into the ventricle, by 
which it is sent through the pulmonary arteries (359, 
369) into the capillaries of the lungs, where the grand 
process of digestion is completed, which commences 
in the mouth (426), and continues all along the living, 
alimentary, and lacteal canals and tubes, till the 
chyle is poured into the veins ; and then no further 
change takes place till it reaches the lungs. 

460. The precise change which is effected in the 
chyle, while in the lungs, is not known, as it always 
goes to the lungs mingled with a large quantity of 
venous blood. It appears pretty certain, however, 
that the chyle which goes to the lungs nearly color- 
less, there becomes red, and is more perfectly animal- 
ized, and more highly endowed with vitality. I sa^ 
more highly endowed with vitality, because it is evi- 
dent that the chyle is in some measure a vital fluid 
before it reaches the blood-vessels (459). As the 
chyle and venous blood, however, are mingled toge- 
ther, and are operated upon by the lungs at the same 
time, I shall embrace the two at once, in my des- 
criptions of the physiology of respiration and circula- 

461. The blood, which is diffused throughout the 
body by the heart and arteries, for the nourishment 
of the whole system, is not all taken up and appro- 
priated in its first distribution, but a considerable 
proportion of it is returned through the veins and 
large venous trunk to the right auricle of the heart 
(368, 369). In consequence, however, both of the 
absence of properties which have been abstracted by 
the arterial capillaries, in the general function of nu- 
trition, and of the presence of other properties which 
have been accumulated in the course of the circula- 
tion, the venous blood returns to the heart, dark and 
full of impurities, and wholly unfitted in its condition 
to supply the wants of the system. Should it be 
forced, unchanged, into the general arterial circula- 
tion, the action of the circulating organs would im- 
mediately become extremely feeble and interrupted, 
nutrition would cease, animal sensibility and consci- 
ousness would be instantaneously abolished, all the 
functions of organic life would falter, and death would 
soon ensue. The venous blood, therefore, must either 
be wholly thrown out of the system as excrementi- 
tious matter, or it must, by some renovating vital pro- 
cess of the organic economy, be restored to its original 
character as arterial blood. Should it be eliminated 
as excrementitious matter, the demand for alimentary 
supplies in the digestive organs would be vastly in- 
creased. The benevolent Creator has therefore estab- 
lished a special economy, by which the venous blood 
is purified and renovated, and perfectly restored to 
its original character, and fitted for supplying the 
wants of the system, equally as well as new-made 
blood ; and in doing this, He has, in a truly wonder- 
ful manner, combined vital function with physical 
and mechanical advantage and convenience. 

462. As soon as the returning blood of the veins is 



poured from the large venous trunks (378) into the 
right auricle of the heart, the walls of that cavity 
contract upon it, azld press it down into the right 
ventricle (369), from which the tricuspid valve pre- 
vents its returning. No sooner does it enter this 
ventricle than its walls also contract upon it, and 
send it through the pulmonary artery and its branches, 
into the capiUary vessels of the lungs, which are rami- 
fied upon the air-cells as I have described (359). 
While passing through these minute vessels, the chyle 
and venous blood undergo those important changes by 
which they both become arterial blood. In regard to 
these changes, physiologists have indulged in exten- 
sive speculations, some of which are exceedingly inge- 
nious and interesting. But it would not be a profit- 
able employment of time to review them on this oc- 
casion ; and therefore I shall only present the con- 
clusions to which I have arrived, after a careful ex- 
amination of the whole subject, merely observing, 
by the way, as a general remark, that with respect 
to respiration, as well as all the other vital functions 
of the body, many physiologists appear to have erred 
by attempting to explain vital phenomena on the 
principles of inorganic chemistry. 


463. It is, doubtless, a matter of general knowledge, 
that, according to modern chemistry, the atmosphere 
is composed of several gases or kinds of air, and a con- 
siderable quantity of water in a state of vapor. Pure 
air, however, according to the statements of chemis- 
try, consists of twenty parts of oxygen gas, and eighty 
parts of nitrogen or azote (99). But by means of the 
chemical changes of composition and decomposition 
which are continually going on in nature, various 
gases are evolved, and become more or less diffused 
throughout the atmosphere ; some of which are too 
subtil to be detected by the closest scrutiny of the 
chemist, and others are so volatile and light that they 
ascend to the upper regions of the atmosphere, where 
they probably undergo new changes and enter into 
new forms. Some, however, enter into combinations 
near the earth's surface, and are of sufficient specific 
gravity or weight to remain in the lower region of 
the atmosphere. Of these, about one per cent, of 
carbonic acid gas, formed by a chemical combination 
of certain proportions of oxygen and carbon, is always 
and universally present. 

464. The oxygen and azote of the atmosphere are 
not chemically combined as in nitric acid, but inti- 
mately mixed together ; so that, when a portion of 
the oxygen of a given volume of air is consumed, the 
remaining oxygen diffuses itself equally throughout 
the whole volume, as fast as the consumption takes 
place. This law of nature, established by a wise and 
benevolent Creator, is of immense importance to all 
living bodies, both animal and vegetable*^ 

466. Now, in regard to the changes.' which take 
place in the lungs, there are certain phenomena or 
facts attending respiration, on which physiologists 
have built their theories of the function. In the 
first place, the venous blood goes from the heart to 
the lungs, with a dark purple color, and unfitted for 
the purposes of nutrition in the system, and returns 
from the lungs to the heart with a bright red color, 
and possessed of all the properties requisite for sup. 
plying the general wants of the vital economy. In 
the next place, the air goes into the lungs composed 
of about seventy-nine or eighty parts of azote, nine- 
teen or twenty parts of oxygen, and one per cent, of 
carbonic acid gas ; and returns from the lungs with 
about the same proportion of azote, five or six parts 
of oxygen, and thirteen or fourteen parts of carbonic 
acid gas. In some way or other, therefore, the oxy- 
gen of the inspired air suffers a great diminution of 
volume in the lungs, and a volume of carbonic acid 
gas is produced equal, or nearly equal, to the loss of 

oxygen. These facts led the chemists to conclude « 
that the venous blood, and perhaps the chyle also, 
give off a quantity of carbon in the lungs, and that 
a part of the oxygen of the inspired air combines 
with the carbon, and forms the carbonic acid gas. 
And as it is a law in inorganic chemistry, that when 
oxygen combines with carbon in the formation of 
carbonic acid gas, heat is always produced, a most 
ingenious and beautiful theory of animal heat has 
been built upon this view of the function of the 

466. Mr. Crawford, who principally matured this 
theory, reasons thus : When the venous blood gives 
off its carbon in the lungs, its capacity for caloric, or 
the substance of heat, is increased ; the carbon thus 
set free instantly combines with a portion of the oxy- 
gen of the inspired air, and forms carbonic acid gas, 
by the process of which combination heat is evolved, 
and that heat is instantly taken up by the increased 
capacity of the now arterial blood ; and as this blood 
is diffused into every part of the system, a&d becomes 
changed into venous blood again, its capacity for 
caloric is diminished and the heat is given off. 

467. This was making the changes effected on the 
blood and chyle in the lungs, and the production of 
animal heat, purely processes of inorganic chemistry. 
And perhaps never was an erroneous theory more in- 
geniously constructed or more plausibly supported. 
But it has been fully ascertained, by numerous ex- 
periments and extensive investigation, that the oxy- 
gen of the inspired air does not combine with the 
carbon of the blood in the lungs to form the carbonic 
acid gas of the expired air ; for this gas continues to 
be expired from the lungs, when nothing but pure 
hydrogen is inhaled : neither does the oxygen enter 
in a free state into the blood, to combine with carbon 
and form carbonic acid gas, and evolve heat, in the 
course of the circulation, as some have suggested. The 
whole chemical theory, therefore, in regard to respir- 
ation and the production of animal heat, is without 
the support of any well established facts requiring 
such an explanation ; and it is certainly contrary to 
all correct notions of the vital operations, and the 
general physiological economy of the living body. 

468. The function of the lungs may be considered 
as twofold. As depurating or cleansing organs, they 
eliminate the impurities of the blood, in a manner 
corresponding with the functions of the external skin 
and the mucous membrane generally (289), and wfth 
all the exbretory organs of the body ; and as organs 
of nutrition they digest the air, and convert a portion 
of it into the substance of the blood. 

469. As depurating organs, the lungs by a vital 
process continually excrete from the venous blood, 
and perhaps also from the chyle, in their capillarv 
vessels, certain substances, the dimination of which 
is necessary to prepare those fluids for the nutrient 
purposes of the system. As soon as the excreted sub- 
stance or substances are thrown into the air-cells 
(353), the matter composing them yields to the affi- 
nities of inorganic chemistry, and issues from the 
lungs in the form of vapor, of carbonic acid gas, etc. 
The vapor thrown from the lungs in this manner, 
sometimes amounts to nearly a quart of water in 
twenty-four hours. A portion of this is supposed to 
come from the chyle. The quantity of carbonic acid 
gas discharged from the lungs in the twenty-four 
hours is also very considerable. This gas is unfit for 
animal respiration, and when inhaled into the lungs 
without a mixture of atmospheric air, it soon caiises 
suffocation, asphyxia, and death. This effect, how- 
ever, is owing to its negative rather than to its posi- 
tive qualities, or to the absence of oxygen, by which 
alone animal respiration is supported ; for carbonic 
acid gas can be introduced freely into the stomach 
without having any of the effects of a poison upon the 
system. It is by the consumption of the oxygen of 



the air, and the generation of this ^as by the burning 
o£ charcoal in an open vessel in a tight room, that life 
is often destroyed ; and for the same reason, a large 
number of people in a close or ill-ventilated room, by 
their continued respiration and perspiration, render 
the air very impure and unwholesome ; and were it 
not for a wise and benevolent arrangement in the 
general economy of nature, in regard to this gas, all 
animals would soon be destroyed by it (143). Being 
specifically heavier than atmospheric air, it sinks 
below the nostrils and mouth of the animal during 
the little pause which follows expiration, and thus is 
prevented from beinsf drawn into the lungs again in 
the succeeding act of inspiration. Descending towards 
the earth, it becomes diffused through the atmos- 
phere, and during the day it is taken up by the vege- 
table organs of nutrition, and decomposed, the oxygen 
being set free and the carbon retained and converted 
to vegetable substance (143). During the night, or 
prevalence of darkness, however, plants, like animals, 
are said to give off carbonic acid ^as. But it is sup- 
posed that their consumption of it during the day is 
sufficient to preserve the atmosphere in a state proper^ 
for animal respiration. 

470. When the blood in the capillary vessels of the 
lungs is purified in the manner I have described, it is 
prepared to receive a portion of the digested and assi- 
milated air. This is also a purely vital process. The 
lungs are constantly receiving fresh supplies of aeri- 
form aliment, which, like the food received into the 
stomach, consists of certain adapted proportions of 
nutritious and innutritions substances (438), and 
although expiration always immediately follows in- 
spiration, yet the lungs are never entirely exhausted, 
but a considerable volume of air alwa^rs remains in 
them, much larger than that which is inhaled at an 
ordinary inspiration.* The air which we expire, 
therefore, is probably very little, if any of it, that 
which was received by the immediately preceding in- 
spiration. But each successive volume of inspired air 
probably displaces an equal volume of the retained air 
which has been acted on by the digestive powers of 
the lungs ; and thus something like an aerial circu- 
lation, or the gradual process of digestion in the ali- 
mentary cavity, takes place in these organs. 

471. If the top of the intestinal tube in a dog be 
tied close to the pyloric orifice of the stomach, so that 
nothing can pass from the gastric cavity into the in- 
testines, and a quantity of proper food suitably mas- 
ticated be introduced into the stomach, that organ 
will convert the nutritious properties of the food into 
chyme, and its lacteal or lymphatic vessels will elabor- 
ate from that chyme a quantity of chyle sufficient to 
answer the immediate demands of the vital economy ; 
and the fecal parts of the food, together with some 
remaining chyme, will then be ejected or regurgitated 
from the stomach, through the meatpipe and mouth. 
In this manner the animal may be sustained for six 
or eight weeks (388). This affords a good analogical 
illustration of the digestive function of the lungs. 
Having but one orifice, they throw off their excre- 
mentitious matter through the same aperture by 
which they receive their aeriform food. 

472. Oxygen is undoubtedly the nutrient property 
of the air (465), and hence it is said that it supports 
respiration (92) ; yet I contend that it never becomes 
incorporated with the blood at oxygen (112), but it is 
digested or decomposed in the vital process by which 
it IS converted into the substance of the blood, and 
becomes a constituent and identical part of it ; and 
then it is not oxvgen nor anything else but blood. 
Nor is it till the vitality of that fluid is destroyed, and 

, its constitutional nature essentially changed, that 
oxygen or any other chemical element can be obtain- 

* According to Menziet and Goodwill, five times the quantity 
of air remains in the lungs after ordinary expiration that is or- 
dinarily expired or inspired at any one time. 

ed from the perfectly healthy blood. The quantity 
of oxygen consumed by an individual is said to vary 
with the nature and degree of exercise, state of mind, 
degree oi health, kind of food, temperature of the at- 
mosphere, etc. Much more is consumed when the 
weather is cold than when it is warm, more during 
digestion than when the stomach is empty, and less 
is consumed when the food is vegetable than when it 
is animal, less when the body is at rest than when in 
action, and less when the mind is calm than when it 
is disturbed. The average quantity, however, is sup- 
posed to be about two pounds and eight ounces, troy 
weight, per day. 

473. That some of those forms of matter which are 
called chemical elements are largely employed in sup- 
plying the wants of the vital economy of the living 
body, and that some of them* are better adapted ta 
supply particular wants, or produce particular effects, 
in that economy than others, is most evidently true 
(139) ; but this is far from proving that those forms 
pass unchanged through the vital processes into the 
vital results, and still less does it prove that the laws, 
which govern those substances as chemical elements, 
in the processes of inorganic chemistry, go with them, 
into the vital domain to control the action of their 
affinities, and the modes of their combination. 

474. In suffering this two-fold function of the lungs, 
the chyle and dark-purple venous blood become con- 
verted into bright-red arterial blood, fitted to supply 
all the wants of the vital economy. And the more 
completelv the function of the lunp^s is fulfilled, th& 
more richly is the blood endowed with those delicate 
properties which gratefully exhilarate every part 
where the living current flows, healthfully invigorat- 
ing all the organs, and giving increased elasticity to 
all the springs of action in the system, causing every 
function to be more perfectly performed, imparting 
buoyancy to the animal spirits (^5), and delightfully 
exciting and facilitating the intellectual operations. 


475. The blood thus purified and renovated in the 
lungs, returns in the pulmonary veins to the heart 
(369, 369), and is emptied into the upper cavity or 
auricle on the left side. The walls of this cavity in- 
stantly contract, and press the blood into the lower 
cavity or ventricle on the same side, whence it is pre- 
vented from returning to the auricle, by the mitral 
valve (369), which is pressed up and closes the open- 
ing between the two cavities. No sooiler does the 
blood enter the left ventricle, than the thick muscu- 
lar w^s of this cavity vigorously contract, and throw 
it into the aorta or great arterial trunk (369), which 
being always full of blood, that which is thrown from 
the heart presses on that which is in the arterial 
tube ; and thus, by the constant action of the heart, 
the column of blood in the aorta is continually moved 
on, in the same manner that a column of water is 
raised in a common pump, till it flows through the 
arterial branches into all the capillary extremities, 
and is thus, with the assistance of arterial and capil- 
lary action, diffused over the whole body (374), im- 
parting nourishment to the bones, cartilages, liga- 
ments, tendons, membranes, muscles, and nerves, and 
supplying the various secretory organs with the 
blood from which they separate, or elaborate their 
lubricating and solvent and other fluids and substan-^ 
ces. And, passing from the capillar v extremities of 
the arteries to those of the veins (378), the unappro- 
priated blood, now rendered dark and impure, or un- 
fitted for the purposes of nutrition (461), is carried 
back to the heart and lungs, to be purified and reno- 
vated in the manner I have described (469, 470), and. 
then thrown again into the general circulation. 

476. The whole quantity of blood in the body of an 
ordinary-sized man, is from three to four gallons. Of 



this, from one-fourth to one-third is supposed to be 
contained in the arteries, and from two-thirds to three- 
fourths in the veins (371>), a large proportion of the 
whole being in the arterial and venous capillary ves- 
sels (313). In civic life, the ventricles of the heart 
in healthy adults contract from seventy to seventy- 
five times in a minute ; and it is supposed that the 
left ventricle throws into the aorta from one to two 
ounces of blood at every contraction, and that a quan- 
tity equal to the whole volume of blood in the body 
passes through the heart as often as once in three 
minutes. In a new-born infant the heart contracts 
about one hundred and forty times in a minute ; in 
the first year of life, about one hundred and twenty- 
four times ; and in the second year, one hundred and 
ten, and in the third, year, ninety-six times in a 
minute. In the decline of life, the contraction of the 
heart diminishes in frequency, and in old age the 
pulse does not exceed sixty in a minute. The rapidity 
of the circulation, however, varies in different indivi- 
duals according to different circumstances, habits, 
etc. In some men the heart regularly contracts more 
than four thousand times in an hour ; in others, less 
than three thousand. This difference, as we shaU 
see hereafter (909 J, as a general fact, depends much 
on dietetic and other voluntary habits. 

477. The blood, like the chyle and other substances 
of the body, has repeatedly been analyzed by the 
chemists, and we have been told the precise quanti- 
ties of the muriate of soda and potash, of phosphate 
of lime, iron, sulphur, etc., contained in it ; but with- 
out the least advantage to physiology, therapeutics, 
or dietetics. On no one of these points has the che- 
mical analysis of the blood thrown the least ray of 
light ; for it is not with a fluid composed on the prin- 
ciples of inorganic chemistry, of certain proportions 
of certain chemical elements, that the physiologist 
or the physician has to do, but with a living fluid, 
elaborated by vital processes, and subject to the laws 
and conditions of vitality. 

478. The blood is most indubitably a living fluid 
(203), and its vitality is susceptible of very consider- 
able increase and diminution. That it has vitality 
in itself has repeatedly been, and may easily be, 
proved by conclusive experiments ; still, however, its 
intrinsic vitality cannot long be sustained out of the 
living vessel to which it belongs. Taken from the 
living vase, it loses its vitality in a few minutes ; but 
if a quantity of blood be confined to a portion of a 
living and healthy artery, its vitality will be preserv- 
ed as long as the healthy vitality of the artery re- 
mains. The preservation'of the vitality of the blood, 
therefore, depends on the living vessels in which it 
flows, or rather on the nerves of organic life which 
preside over the functions of those vessels (219), and 
the degree of vitality in the blood varies with the 
general condition of these nerves, and the general 
condition of these nerves depends very much on the 
character and condition of the blood. 

479. If the quantity of blood in the system be ex- 
cessive, there is a tendency to special or general con. 
gestion, inflammation, and death. On the other hand, 
if the quantity of blood be too far reduced, the func- 
tional energy of the nervous system is diminished, 
the conservative power of the blood-vessels is impaired, 
and the intrinsic vitality of the blood is commensu- 
rately lessened. Hence, if a healthy robust man be 
copiously bled, and then several smaller portions of 
blood be taken from him at short intervals, each suc- 
cessive portion will lose its vitality sooner than the 
preceding one. The specific gravity of the blood is 
little more than that of water : it has been afiSrmed 
however, that * the more perfect the organization of 
the blood, or the higher the degree of vitality it pos- 
sesses, the greater appears to be its specific gravity.' 

480. By some physiologists the blood is considered 
a homogenous fluid, whOe others assert that it is a 

complicated compound of all the substances which 
compose the various solids and fluids of the living 
body ; the substances of the bones, cartilages, liga- 
ments, tendons, membranes, muscles, nerves, bile, 
salivary, gastric, pancreatic, and other fluids, etc., 
ready formed, and all mixed up together in the blood, 
like the materials oi the world in the fabled chaos ; 
and all that is further necessary for the arrangement 
of these materials into the several structures and or- 
gans of the body, is to have the blood pass through 
certain strainers which are so constructed and situa- 
ted as to separate out and retain each material in its 
proper place. But this is obviously an expedient 
to cover human ignorance with the guise of science ; 
a purely hypothetical attempt to explain the opera- 
tions and results of the vital economy upon chemical 
and mechanical principles. 

481. While the blood is healthfully flowing in its liv- 
ing vessels, it is impossible for us to investigate its pro- 
perties ; and it is equally impossible for us to know 
how soon our meddling with it may effect essential 
changes in its character. The furthest, therefore, 
that our knowledge of the living blood extends, is 
that when first taken from the living and healthy 
vessels, and examined under a microscope, it is found 
to be composed of a fluid containing innumerable 
minute globules, which are surrounded by a kind of 
pellicle or tunic of coloring matter (459, 474). A 
substance called fibrin is also said to be contained in 
the blood ; but there is reason to believe that the 
fibrin is nothing more than an arrangement of the 
globules just named, divested of their coloring matter, 
and that the fibrin as such is not to be found in the 
actively circulating blood. 

482. ^V^len taken from the living vase and permit- 
ted to stand a short time, the blood coagulates, or a 
portion oi it gathers into a thick clot called the cras- 
samentum, and the remaining portion is a thin, tran- 
sparent fluid of a greenish and yellowish appearance 
and saltish taste,* and is called serum. By washing 
the clot freely in water, its coloring matter is removed, 
and it becomes white and has a fibrous appearance. 
When putrefaction commences in the blood taken 
from the living body, it attacks rather the coagulum 
than the serous portion, aud this is true also of the 

488. This is as far as the physiologist can push his 
analysis of the blood ; and this, taken in connexion 
with several important facts and phenomena which 
constantly take place in the living system, justifies 
the conclusion that the blood is not a homogenous 
fluid, but naturally consists of innumerable globules 
or corpuscles of animalized matter held in a fluid 
state by an aqueous menstruum, or diluent, and that 
the vitality of the blood wholly resides in the 

484. I have said (440), that water appears to pass 
from the stomach into the circulation with very little 
if any change ; and it is a well known fact, that all 
the absorbent vessels of the body pour their contents 
of every kind, whether assimilated or not, whether 
salutary or deleterious, into the veins. It is also 
well known that large quantities of water, holding 
saline substances in solution, may be injected directly 
into the veins of living animals without destroying 
life. Castor-oil and other medicinal substances may 
likewise be introduced in the same manner ; and 
alcohol and other poisonous substances pass uuchang- 
ed from the stomach, and mingle with the blood (448). 
Indeed alcohol is sometimes present in the blood in 
so large a quantity and so concentrated a form, as 

« It is by no means certain that the saltish taste of the semm 
of the blood is not wholly attributable to the dietetic use of salt. 
Dr. James, formerly of the United States army, informed me in 
the summer of 1836, that the soldiers on the remote western fron- 
tiers used no salt with their food when he was with them, and 
that he foimd their sensible perspiration to be as free from the 
taste of salt as pxire water. 



not only to be readily detected bv the senses of smell 
and taste, but also to bum freely with a blue flame 
when touched by a lighted candle. When death is 
caused by lightning, it is well known that the blood 
remains in a fluid state incapable of coagulating ; and 
in several forms of malignant putrid fever, the corpus- 
cles of the blood are broken down and lose the power 
oC coagulating (482); and in some instances there are 
manifest evidences that putrefaction has commenced 
in the globules of the blood before the life of the body 
is extinct. 

485. All these facts seem to prove conclusively, 
that the blood cannot be a homogenous fluid, and 
that the serum of the blood cannot possess any de- 
gree of vitality ; and they leave little room to doubt, 
that what is called ^he coloring matter which sur- 
rounds the vitalized globules (481), is intended to 
shield them from the pernicious properties or influences 
-of mch foreign matters as may find their way into the 
blood-vessels y and become mixed with the serum of the 
blood. While the animalized corpuscles remain in 
the lacteals and other vessels, where, in the normal 
state of the system, only assimilated fluids are per- 
mitted to enter, they are not invested with those pel- 
licles or coverings which become red in the lungs, or 
at least not until they reach the thoracic duct (459), 
and are about to pass into the veins ; and when they 
finally enter into the arrangements of organized struc- 
ture, they are ag^in divested of those tunics; and 
hence it appears that they ar'e only thus covered 
while travelling in the common highway of the circu- 
lation, where they are continually exposed to the con- 
tact and influence of foreign and unassimilated sub- 

486. It is probably from the serous portion of the 
blood mainly, that the excrementitious secretions 
and exhalations are made ; and the impurities which 
sometimes accumulate in the blood from special or 
general derangement of function, are probably con- 
tained in this menstruum; and it is possible that they 
exert their deleterious influence first on the nervous 
tissue of the blood-vessels (230), and through them 
on the nerves of organic life generally, producing ir- 
ritation and morbid affection, which involves the 
blood-vessels, and by them is communicated to the 
living globules of the blood, and thus producing a 
general fever, which is modified in type and symptoms 
by various circumstances. Hence, the intense thirst 
which usually attends a fever, and which may be an 
instinctive demand for water to displace the offensive 
serum and allay the preternatural heat and action ; 
and hence also the interesting fact, than pure soft 
water, freely administered, is decidedly the most ef- 
ficient febrifuge in nature. The most violent fevers 
have been subdued by it with astonishing rapidity, 
when the ordinary means of medical practice had 
proved utterly ineffectual. I confess, however, that 
this is mere speculation ; but it seems to me to be cor- 
roborated by all known facts relating to the subject. 
Yet I do not by any means suggest this as a univer- 
sal theory of fever, but merely as one of the means by 
which fever is induced. 


487* The temperature of the human blood, I have 
said (129), is, in a healthy state of the body, ordin- 
arily about 98 degrees Fah, It rises above and falls 
below this point, some few degrees in particular states 
of disease ; but in the vigorous health of the body, 
the differences in external temperature seem to have 
very little effect on it, the blood being always about 
the same temperature whether the individual is tra- 
veiling upon the polar seas or under the meridian 

488. Many attempts have been made to account for 
animal heat, on the principles of inorganic chemistry ; 
and no one of them, as X have already observed (466, 

467), has been more ingeniously constructed and more 
plausibly supported than that of Mr. Crawford, and 
no one has been so generally received. And even 
yet, though the essential defects of Mr. Crawford's 
theory have been demonstrated, many physiologists 
seem disposed to cling to the notion that respiration 
is in some way or other the immediate source of ani- 
mal heat, because there appears to be a close relation, 
say they, between the degree of heat in the body and 
the quantity of oxygen consumed. But this reason- 
ing appears to me to be very inconclusive. We have 
seen that the vital properties which constitute the 
functional powers of all the tissues and organs in the 
body, are rapidly exhausted by action, and that they 
are replenished entirely by the constant supply of 
fresh portions of arterial blood (376). This supply 
being withheld, the muscles soon loose their suscepti- 
bility to the stimulus of motion, and their power of 
contractility ; the sensorial power of the nerves is 
immediately suspended, and the nervous power is 
very soon lost (461). We have seen also, that the 
blood cannot be purified, renovated, and fitted for the 
replenishment of the exhaustions of the system, with- 
out the function of respiration, and that oxygen is 
essential to this function (472). In this view' of the 
subject, oxygen is certainly essential to the calorific 
function or the production of animal heat, but not as 
a chemical element depending on its chemical proper- 
ties and combinations (139). 

489. Animal heat, like voluntary animal phospho- 
rescence and electricity, is most unquestionably a re- 
sult of vital function, depending immediately on the 
vital properties and functional powers of the nerves 
of organic life (228). Whatever, therefore, impairs 
the health of the system of nerves, diminishes the 
power of the living body to regulate its own temper, 
ature. Hence spirit-drinkers, except when under the 
direct influence of the alcoholic stimulus, have less 
power to resist cold, in proportion as the health of 
their nervous system has been impaired by the poi- 
son. Indigestion also, and all other difiiculties of the 
stomach and intestinal tube, connected with the gene- 
ral condition of the nerves of organic life, diminish 
the vital powers of reaction against cold. Whether 
the production of animal heat, therefore, be a process 
of secretion, or a function peculiar to itself, or nearly 
resembling that of animal phosphorescence and elec- 
tricity, I do not pretend to say ; but I am entirely 
confident that it is purely a vital function, depending 
inunediately on the vital properties and functional 
powers of the nerves of organic life. 

490. The relaxing and debilitating effects of con- 
tinued heat, always diminish the power of the body 
to sustain sudden and severe cold. They also dimin- 
ish the powers of digestion and general nutrition, 
and render the system more susceptible of injury 
from dietetic irregularities and excesses ; and, on the 
other hand, except in special cases of disease, con- 
tinued cold weather, if it be not too intense, invigor- 
ates all the functional powers of the body, increasing 
greatly its ability to generate heat and maintain a 
uniform temperature, and commensurately increasing 
the powers of digestion and general nutrition ; but 
sudden and extreme cold depresses all the physiologi- 
cal powers of the system (229). 

491. Heat, I have said (129), radiates from the 
living body in the same manner as it does from inor- 
ganic bodies ; hence, as a general fact, the tempera- 
ture of living bodies is lower near the surface than in 
the more central parts ; but this by no means sus- 
tains the conjecture that the calorific function is pecu- 
liar to the internal parts. It is probably not peculiar 
to any particular part of the system, but is as univer- 
sal as the distribution of the nerves of organic life 
and the blood-vessels. 

492. The interests of the vital economy seem to 
require that the blood under the vital control should 



be easily preserved in a state of fluidity, and at the 
same time be capable of becoming solid with ease. 
And it appears from numerous experiments that the 
blood most readily coagulates at its natural tempeVa- 
ture of 98 degrees Fan,, and that any considerable 
variation from this point impairs and even destroys 
its coagulating power. 


493. The blood being distributed by the arteries 
to every part of the body which requires nourishment 
(476), is regularly appropriated according to the 
wants of the several parts ; and with most undeviat- 
ing accuracy and integrity, every structure is fur- 
nished with fresh supplies of its own proper substance. 
The bones, cartilages, ligaments, tendons, membranes, 
muscles, and nerves, all continually receive new por- 
tions of homogenous matter, elaborated by the vital 
processes from one and the same current o£ blood. 
How these ultimate processes of assimilation or struc 
ture are effected is whoUy unknown. Various con- 
jectures have been advanced on the subject, but they 
have begun and ended in guessing and hypothesis. 
I have already alluded to the notion (480), which 
attributes to the ultimate vessels the office of strain, 
ers, that merely separate from the blood substances 
already formed in that common fluid ; yet it is well 
known that not a trace of gelatin has ever been found 
in the blood, although this substance probably enters 
more extensively into the solid forms of matter than 
any other in the body. Some physiologists, as I 
have said (375), have imagined that there is a system 
of vessels called exhalants connected with the capil- 
lary system, which perform the ultimate processes of 
nutrition. Other and very eminent pnysiologists 
suppose that the capillary extremities of the arteries 
secrete and deposite in its proper place and manner 
the substance of each particular structure in the 
body; and they assure us that, with the utmost 
powers of the microscope, they are unable to detect 
any difference between the vessels which secrete one 
substance and those which secrete another ; that even 
those which supply the teeth and those which support 
the brain appear extremely alike ; and yet the sub- 
stances which they secrete from the same blood are 
as extremely unlike as any two in nature. The ves- 
sels which form and nourish the cartilages, ligaments, 
tendons, serous membrane, etc., are said to circulate 
only white blood (185), and some have supposed it is 
because they are too small to circulate the red glob- 
ules ; but this is a mere conjecture, and the reason 
assigned is of quite too mechanical a nature for a phy- 
siological explanation. 

494. From the commencement of chymification to 
the ultimate function of structure, therefore, and in- 
deed to the ultimate function of decomposition and 
elimination of the effete or worn out matter of the 
body, all the changes are unquestionably effected by 
the processes of vital chemistry, which decompose the 
simplest known forms of matter (139), and whose 
analytical and synthetical operations are governed by 
laws peculiar to vitality, and in direct opposition to 
the affinities of inorganic chemistry (121 — 123). 

495. Besides supplying the ordinary wants of the 
body by the general function of nutrition, the vital 
economy possesses the power, to a certain extant, of 
repairing the injuries which are done to it by phy- 
sical violence. If a bone be broken, or a muscle or 
a nerve be wounded, and if the system be in a proper 
state of health, the vital economy immediately sets 
about healing the breach. The blood which flows 
from the wounded vessels, by a law of the economy, 
coagulates in the breach, for the double purpose of 
stanching the wound, and of forming a matrix for the 
regeneration of the parts. Very soon minute vessds 
shoot out from the living parts into the coagulum of 
the blood, and immediately commence their opera- 

tions, and deposite bony matter where it is required to 
unite a fractured bone, and nervous substance to he^ 
the wounded nerve, etc. But the vital economy 
seems not to possess the power of reproducing the true 
muscle (201), and therefore when any fleshy part has 
been wounded, its breach is repaired by a gelatinous 
substance which gradually becomes hard, and some- 
times assumes something of the fibrous appearance 
It however so perfectly unites the divided musdles as 
to restore its functional power. 

496. In this wonderful process of healing, the little 
vessels employed in furnishing the matter for the sev- 
eral structures seem to know precisely where to com- 
mence and where to end their labors ; and unless dis- 
turbed and driven to irregular operations by irritating 
causes, they never leave their labor incomplete, nor 
go beyond their proper bounds. But under the con- 
stant abuses of the body, when the nerves of organic 
life are continually tortured, and the vital economy 
generally disturbed, by the unhealthy habits of the 
individual, not only in the process of healing a woun- 
ded part, but in the ordinary function of nutrition, 
substances will be misplaced or imperfectly elaborated, 
and diseased structure will be the result. 


497. The common current of blood from which the 
solids of the body are elaborated, is also the source- 
from which the different vessels (331) and foUides 
(333) and glands (334) exhale or secrete (330) the- 
aqueous fluid or vapor which everywhere perspires 
from the external skin, and from the mucous mem- 
brane of the alimentary cavity (339) and of the lungs 
and nose and ears and eyes and every other part ; and 
that which exhales from the serous membrane of the 
closed cavities (178), and moistens and lubricates the 
heart (368) and all other organs and parts in the thorax 
and abdomen (175); and that which moistens the 
brain (272) and the spinal marrow ; and the glairy 
fluid which lubricates the joints (185J and the tendons, 
etc. (195) ; and the serous fluid of the proper cellular 
tissue (171) ; and the adipose matter (178) of the same 
tissue (498) ; and the marrow of the Dones (179) ; and 
the humors of the eye (409) ; and the mucus (333) 
which everywhere lubricates the surface, and imbeds 
and protects the delicate vessels and nerves of the 
mucous membrane (339) and external skin (187); 
and the oily matter which anoints the skin and hair 
(421) ; and the wax of the ear (333) ; and the tears 
(413), and the saliva (340), and the gastric juice (332), 
and the pancreatic fluid (447), and the bile (451), and 
the secretion of the kfdneys, and every other secreted 
and excreted fluid and substances of the body, which 
are subservient to the lubricating and solvent purposes 
of the vital economy, or are eliminated from the vital 
domain for the purposes of purification. But how 
these secretions are effected, we know as little as we 
do how the substances which enter into the solid struc- 
tures are produced. All that is known on the subject, 
however, warrants the conclusion that the vital forcet. 
possess something like a transmuting power (62), at 
they continually elaborate from a few kinds, and even^ 
from a single article of food and the atmospheric air, 
all the different substances of the body, with natures 
and properties so diversified, so different ; and which 
when analyzed by the chemist, afford many substan- 
ces which cannot be accounted for from any thing- 
contained in the blood, nor upon any known princi- 
ples of chemical analysis and combination. All these 
substances have been repeatedly analysed, and the 
chemical results precisely stated, but without any- 
advantage to physiology or therapeutics (431). 

498. Concerning the adipose matter, or fat, which 
transudes from the arterial capillaries, or is in some 
other manner deposited in many parts of the cellular 
tissue (178, 497)> different opinions have been enter- - 
tained. It is contained in little cells, which varyt* 



exceedingly in size, form^ and disposition, and which 
do not communicate with each other. It is said to be 
always found in the cellular tissue of the orbits of the 
eyes, the soles of the feet, the pulp of the fingers and 
that of the toes ; and to h^ frequently found, and some- 
times in great abundance, in the cellular tissue under 
the skin, and in that which surrounds the heart, 
kidneys, etc. ; while in the eyelids, the interior of the 
skuUt'of the brain, the eyes, ears, nose, lungs, intesti- 
nal canal, glands, and some other parts, it is never 
found, except as the effect of disease. The quantity 
of this oily matter or fat in the human body varies 
greatly in different individuals, and in the same indi- 
vidual at different times (178). In some instances it 
constitutes a very considerable proportion of the bulk 
and weight of the whole body. Various opinions have 
been entertained in regard to the use of this substance 
in the animal organic economy. In the orbits of the 
eyes, the soles of the feet, and other parts where it is 
most invariably found, it is supposed to serve the pur- 
pose of the elastic cushions, giving facility to move- 
ments, diminishing the effect of pressure, etc. Under 
the skin, it is supposed, as a non-conducter of heat, 
to assist in preserving the natural temperature of the 
body, and protecting the vital domain from the effects 
of severe cold ; and generally, it is thought to be sub- 
servient in some measure to the lubrication of the 
solids ; and also to prevent excessive sensibility. It 
is, moreover, a prevailing opinion among physiologists, 
that the disposition of this matter in the cellular tissue 
is a provision of nature against the emergencies of 
famine. They suppose that when, by any means, the 
food of an animal is long cut off, as in the case of hi- 
bernation or torpor through the winter, the vital eco- 
nomy lays hold of its adipose deposites, as bees do upon 
their honey, and reconverts it into blood for the nour- 
ishment of the system ; and this is inferred from the 
fact that the bear and other hibernating animals, on 
entering into the torpid state for the winter, have gen- 
eriilly a considerable quantity of fat in their bodies, 
and that when they come out in the spring, it is all 
gone, and they are exceedingly lean. But this does 
not appear to be conclusive. If an ox be stall-fed till 
he becomes very fat, and then put to hard labor for 
seveiid months, he will lose a large proportion of his 
fat, even though he be as highly fed during the whole 
time of his labor as he was in the stall, and receive all 
the food that he will eat, and all that his vital economy 
can healthfully dispose of. But in this case it will 
hardly be said that the adipose matter is re-absorbed 
for the nourishment of the system. Again, if the fat 
be designed for the nourishment of the body during 
protracted fasts, etc., then if a very fat man, in the 
enjoyment of what is ordinarily considered good health, 
and a lean man in good health, be shut up together, 
and condemned to die of starvation, the fat man ought 
to diminish in weight much more slowly, and to live 
considerably longer, than the lean man ; but directly 
the contrary of this is true. The lean man will lose 
in weight much more slowly, and live several days 
longer than the fat man, in spite of all the nourisn- 
ment which the latter may derive from his adipose 

499. That the adipose matter of perfectly healthy 
bodies, like the marrow of the bones (179) is subser- 
vient to some important purposes in the organic econ- 
omy, cannot be doubted ; but it is not necessary to 
infer from any known facts relating to it, that its* ex- 
tensive accumulation in the cellular tissue is a provi- 
sion of nature for nutrient purposes, nor that it is 
employed for such purposes during long fasts. We 
have seen (314) that in tne grand operations of the vital 
economy, the two great processes of composition and 
decomposition are continually going on : new matter 
is constantly added by the general function of nutri- 
tion to every structure and substance of the body, and 
old matter is constantly withdrawn and eliminated by 

the general function of absorption and excretion, from 
every structure and substance. In a perfectly healthy 
state of the system, while the functional power and 
integrity of all the organs is preserved, a nice equil- 
ibrium is always maintained between the two great 
processes. But if from excessive alimentation, want 
of exercise, or any other cause, this equilibrium be 
destroyed, and the function of nutrition becomes ex- 
cessive, disease in some form or other must speedily 
result, or the vital economy must have some extraor- 
dinary mode of relief. More nutritious matter is re- 
ceived into the vital domain than the wants of the vital 
economy demand, and more than its powers can regu- 
larly dispose of. None of the regular tissues or struc- 
tures of the system can incorporate it, and it cannot 
be eliminated from the vital domain as fast as it is 
received. In this exigency it must be disposed of in 
the safest manner possible, as a temporary resource. 
The cellular tissue, we have seen (168), is' the lowest 
order of animal structure ; the lowest in vital endow, 
ment and functional character : and of all the forms 
of this general structure, that in which the adipose 
matter is deposited (178), is the lowest species. In 
the cells of this loose tissue, which is simply emplo} ed 
as a kind of web to connect other and more important 
tissues and pjirts (171), the vital economy, therefore, 
may, with greatest safety, in its particular emergen- 
cies, deposite for a time whatever substances it is 
obliged to dispose of in the most expeditious and con- 
venient manner, and which it is not able to eliminate 
from the vital domain ; for in these cells, such substan- 
ces are at the greatest remove from any important 
vital power or function that they can be within the 
domain; and hence it is that such substances are 
deposited in this tissue ; and some of the substances 
which are deposited here, and in some cases retained 
for years, are of the most deleterious character, as we 
shall see hereafter (1265). Is it not obvious, therefore, 
that the adipose matter which results from excessive 
alimentation, is temporarily deposited in the cellular 
tissue as a necessary expedient of the vital economy 
in its emergency? 

500. It is a general law of the vital economy, that 
when by any means the general function of decompo- 
sition exceeds that of composition or nutrition, the 
decomposing absorbents alway first lay hold of and 
remove those substances which are of least use to the 
economy ; and hence all morbid accumulations, such 
as wens, tumors, abscesses, etc., are rapidly diminish- 
ed and often wholly removed under severe and pro- 
tracted abstinence and fasting. When by an excess 
of the general function of nutrition, a considerable 
quantity of adipose matter has been deposited in the 
cellular tissue, therefore, if active exercise be consid- 
erably increased, or the quantity of food be consid- 
erably diminished, the decomposing and eliminating 
organs of the system, by all that their functions are 
relatively increased upon that of nutrition, will be 
employed in first removing the adipose matter, in 
order to restore the system to the most perfectly 
healthy condition. 

501. The accumulation of adipose matter in the hu- 
man body, therefore, always evinces more or less of 
diseased action in some of the organs concerned in the 
general function of nutrition, and can only be carried 
to a very limited extent without degenerating into 
serious disease, terminating either in morbid obesity, 
dropsy, or apoplexy, or reacting with violence on some 
of the organs belonging to the digestive apparatus. 
Hence the notorious fact, that almost every animal 
which is fatted and killed for human food, is actually 
in a state of disease when butchered. It is extremely 
difficult, indeed nearly impossible, to find in the butch- 
ers* markets of any of our cities, a perfectly healthy 
liver from a fatted animal ; and it is by no means an 
uncommon thing for fatted hogs to die of disease when 
just about to be killed for the market. 




602. But since, by the general function of nutrition, 
new matter is continually supplied to every structure 
and substance in the body, from the commencement 
of our existence till death closes our temporal career, 
why do not our bodies continue to increase in size as 
long as we live ? Why should they grow from the infan- 
tile form to the stature of manhood, and then entirely 
cease to g^ow, and remain, with slight variations of 
bulk, at a fixed size through life ? The general econ- 
omy of nutrition by which the body attains to the or- 
dinary stature of man, so far as we can perceive, con- 
tinues its operations through life. What then de- 
fines the proportions of our bodies and fixes the limits 
of our growth ? Human science can make no deter- 
minate reply to these interrogations; and in his at- 
tempts to answer them, the physiologist can only rea- 
son from the general laws peculiar to living bodies, 
and from the phenomena, facts, and analogies, which 
indicate the laws that govern the development and 
determine the form and size of all organized bodies. 
My own views on this interesting point will be pre- 
sented in a subsequent lecture. Be it remembered, 
however, that the difficulty in the case is not in account- 
ing for the matter which is constantly supplied to the 
body by the function of nutrition. Because, as we have 
just seen (499), there is in all living bodies an economy 
of decomposition and elimination as extensive as that 
of nutrition. But this economy is in active operation 
during the whole period of growth, as well as in sub- 
sequent life ; and the question is, why, under the active 
and simultaneous operations of the composing and de- 
composing processes, the body should grow to a cer- 
tain size, and then entirely cease to grow, and the two 
processes, as a general fact, balance each other ever 
after ? — or if they do not, disease in some form or 
other necessarily results. In some rare instances, it 
is true, the human body continues to increase in bulk, 
till it becomes an enormous and shapeless mass, as in 
the case of Daniel Lambert and others. But these 
are always cases of disease, and the subject seldom 
reaches the middle period of life. Indeed, as I have 
said (601), all obesity or corpulence is a species of dis- 
ease, and denotes a want of integrity in some of the 
functions of the system. 


503. The general process of decomposition is sup- 
posed to be effected principally by the lymphatics pro- 
per (387, 388), which, as we have seen (386), arise 
from every surface and portion of the body ; so that 
there is scarcely a particle of matter belonging to the 
whole organic system which is not within the reach 
of their action ; and they are supposed to be contin- 
ually acting on every structure and substance in the 
body where the function of nutrition is performed, 
gradually decomposing and resolving to a limpid fluid 
called the lymph, the hardest bones as well as the soft- 
est structures and still less consistent secretions and 
fluids of the system. And thus, by the constant and 
regular operations of the nutritive organs on the one 
hand, and the lymphatics on the other, every structure 
in the living body is continually and simultaneously 
undergoing the processes of composition and decomp<>- 
sition, of renovation and decay (314, 499). Particle 
by particle of new matter is constantly added to every 
structure, from the fluid blood; and at the same time, 
particle by particle of old matter is constantly absor- 
bed from every structure, and converted to the fluid 
lymph. So that while the organic constitution and phy- 
siological identity of every structure and of the whole 
system remain permament through life, a continual 
change is taking place in the particles of matter of 
which our bodies are composed ; and, according to the 
estimate of some physiologists, an entire change of all 
the matter in our bodies is completed as often as once 
in seven years (314). 

604. Besides thus regularly absorbing the substance 
of the various structures, secretions, exhalations, etc., 
within the precincts of the vital domain, the lymphatics 
are also supposed to absorb the pus and other kinds 
of matter which disease may cause to form or accu- 
mulate in any part of the system. If fluids accumu- 
late in any of the closed cavities, these vessels are 
supposed to be the organs by which they are taken 
up and removed; and it is likewise supposed by some 
that they are the organs which in the lungs and ex- 
ternal skin absorb the infectious and pestilential pro- 
perties of an impure atmosphere, and other foreign 
matters. But this last opinion may be considered 
questionable (441, 442). 

605. The lymph has been regarded by some physi- 
ologists as wholly excrementitious matter, which is 
returned to the circulation only for the purpose of 
being presented to the excretory organs which elim- 
inate the impurities of the blood. Others consider 
it as of a very different character and destiny. 
They say that the l^phatics, like the lacteals (466), 
possess an assimilatmg power to a high degree, and 
that all the substances which they absorb of every de- 
scription, are converted into a fluid closely resembling 
the chyle (459), but of a more refined and sublimated 
quality ; and that it is returned to the pulmonary and 
general circulation, to be appropriated to the most 
delicate and elevated purposes of nutrition. The cor- 
rectness of this opinion, however, is somewhat doubt- 
ful. The lymphatics evidently possess an assimilat- 
ing power (441), by which they convert many, if not 
all, of the substances that they absorb, into a nearly 
homogenous fluid, which mingles with the chyle in 
the thoracic duct, and passes with it into the blood- 
vessels (476). And when supplies of food in the ali- 
mentary canal are exceedingly small or entirely cut 
off for a considerable time, the lymphatics unques- 
tionably become much more active than usual, and 
prey upon the adipose and other substances of the body 
(500), forming a lymph which may have many of the 
characterestics of the chyle and blood, and which may, 
to some extent, in such an emergency, serve the pur- 
poses of nutrition. But in the ordinary and iindi8« 
turbed operations of the vital economy, when the ali- 
mentary organs are duly supplied with food, it is pro- 
bable tnat the lymph, formed from the decomposed 
matter of the body, is mainly if not entirely an excre- 
mentitious substance. 


606. The impurities which are continually accumu- 
lating in the blood, by the return of the worn-out 
matter of the body to* the circulation, and by the 
absorption of such substances as are unfitted for the 
wants of the system, are incessantly eliminated or 
expelled from the vital domain by the excretory organs 
constituted for the purpose. The lungs, as we hare 
seen (479), are largely concerned in this work of 
purification. The liver (460) is associated in the same 
general function ; and the kidneys excrete a large pro- 
portion of the effete matter and other impurities of 
the blood. The raucous membrane of the alimentary 
canal also participates to some extent in this oflice; 
but the external skin (331) probably exceeds any other 
organ, and it has been supposed to exceed all the other 
depurating organs in the system, in the quaniiiy of 
matter which it eliminates. It is in some measure a 
respiratory organ, corresponding in function with the 
lungs (479). Like these, it continually consumes 
oxygen, and eliminates carbonic acid gas* and imper- 
ceptible vapor; and at times pours forth a flood of 
sensible perspiration. Foreign and unassimilated sub- 
stances absorbed from the alimentary cavity are large- 
ly eliminated from the vital domain by the skin ; and 
the decomposed matter of the body' is continually 
passing off through this portion of the g^eat limiting 
membrane (330). Since the commencement of the 



seventeenth century the opinion has generally pre- 
vailed, which was advanced by Sanctorius, that the 
skin ultimately throws off, in the form of insensible 
perspiration, something more than one-half of all the 
matter which enters the vital domain. Some modern 
physiologists have questioned the accuracy of this 
estimate; but it is admitted on all hands, that the 
skin is one of the most important depurating organs 
of the system, and that its healthy condition and 
functional integrity are of immense importance to 
human health and comfort. 

d07* The depurating organs, as I have stated (289), 
reciprocate with each other in function to a consider, 
able extent, even in the healthy state of the body, and 
in a diseased condition vicarious function is often at. 
tempted. Copious perspiration diminishes the secretion 
of the kidneys, and on the other hand a suppression 
of the cutaneous function generally increases that of 
the kidneys. The skin and lungs reciprocate in the 
same manner. Excessive exhalations and excretions 
of the alimentary canal also frequently result from a 
suppression of the function of the skin, and, by what- 
ever cause induced, they are always attended with 
cutaneous depression. Biit the welfare of the particular 
parts, as well as of the whole system, requires that 
each organ should uniformly and vigorously perform 
the full measure of its own duty ; because frequent 
excesses arising from an undue determination of fluids 
to any one part, lead to debility of the part, and often 
result in impaired function, imperfect assimilation, 
local disease, and general injury and death. In this 
manner, sudden suppressions of the functions of the 
skin often lead to diabetes and pulmonary consump. 
tion, by causing undue determinations to the kidneys 
and lungs, and inducing inflammation and permanent 
disease in those organs. The liver also suffers from 
all want of integrity in the other depurating organs; 
and its derangements com^iel the skin, and indeed the 
whole system, to make an effort to throw off the matter 
which it should have eliminated. Still more exces- 
sively morbid and extravagant attempts at vicarious 
function take place when the mammary glands and 
other organs endeavor to perform the duties of the 
kidneys. But cases of this kind are very rare ; fre- 
quent enough, however, to show the wonderful resour- 
ces of the vital economy in extreme emergencies, and 
also to demonstrate the great importance of health 
and integrity in each and every organ. 


608. In the most healthful and correct performance 
of their functions, the several organs of the body ne- 
cessarily suffer some waste of substance as well as 
expenditure of functional power (376). But while th e 
general economy of nutrition is properly sustained, 
the replenishment keeps pace with the exhaustion. 
By excesses and irregularities, however, and every 
other means by which the constitutional laws and 
jfiinctional relations of the several organs are violated, 
not only is the system, as a whole, made to suffer, but 
the particular organs are often made the seats of local 
disease and suffering. 

^09. By painful experience, most of the human 
jbrnily who have numbered twenty years, know that 
the teeth may become the seats of distressing disease 
and decay ; the g^ms may become softened and flac- 
cid, and ulcerous, and otherwise diseased. The tongue 
and other parts in the mouth are subject to dis- 
ease in a variety of forms. The salivary fluid and 
mucous secretions may be rendered extremely acrid 
and irritating to the parts over which they pass ; the 
salivary glands may become inflamed, enlarged, indu- 
rated, and cancerous; the nose, fauces, windpipe, 
meatpipe, and other surrounding parts, are liable to 
many distressing forms of disease. The lungs are 
subject to inflammation, ulceration, and general decay; 
the heart and blood-vessels are liable to enlargements. 

ruptures, ossification, and a variety of other forms of 
disease. Derangement of function, formation of cal- 
culi, chronic inflammation, change of structure, decay 
of substance, etc., may take place in the liver, kidneys, 
and other glands. In short, there is not an organ, 
nor tissue, nor substance, in the whole vital domain,* 
which may not become diseased, and prove the source 
of death to the body. The bones (186) may become 
dry and brittle, or they may ulcerate or mortify. 
The cartilages (185), ligaments (188), and tendons 
(195), may also become dry and brittle, and lose their 
elasticity, and ossify or be destroyed; and the nerves 
and muscles may suffer a change of structure and de- 
cay of substance. 

610. There are many external and foreign causes, 
as well as internal disturbances, by which these dis- 
eases are induced, and which act upon the system at 
different points and in various modes. But the ali- 
mentary cavity is the principal avenue through which 
the causes of disease commit their depradations on the 
vital domain; the stomach is peculiarly a centre of 
irritation and starting point of disease to the whole 
body. It is continually liable to be disturbed and 
irritated in itself, and always communicates its irrita- 
tions more or less extensively and powerfully to other 
organs (297, 298). The means by which its own 
function is disturbed and impaired, and itself made 
the seat of disease, are very numerous. Substances of 
every kind, which are not adapted to the wants of the 
vital economy, if introduced into the stomach, become 
the causes of a degree of irritation, always propor- 
tionate to the offensiveness of their character. Ali- 
mentary substances which are in themselves proper, 
if introduced into the stomach in an improper quan- 
tity or condition, or at an improper time, or without 
suitable mastication and insalivation (426), necessarily 
become the causes of irritation, leading to local and 
general disease. The passions of every kind, and es- 
pecially the painful and the violent, all mental ex- 
citements, and severe mental application (304), more 
or less affect the condition and function of the stom- 
ach, and often most injuriously ; and if frequently re- 
peated or long continued, they debilitate the organ, 
and develope in it a high degree of morbid irritability; 
sometimes inducing inflammation, chronic and acute. 
In short, whatever is unfriendly to the vital properties, 
or impairs the nervous power and muscular contrac- 
tility of the stomach (444), or disturbs its function and 
deteriorates its functional results, always leads to dis- 
ease of the organ itself, and tends to induce morbid ir- 
ritability and sympathy, inflammation, thickening of 
its coats, softening and change of structure in the mus- 
cular and nervous tissues, scirrhus, cancer, etc. And 
it is a remarkable fact, that when the integrity of the 
organic sensibilities and sympathies of the parts is 
greatly impaired or destroved by improper dietetic 
habits (296), as is universally the case in civic life, ir- 
ritations, functional derangements, and disease even 
of the most fatal character, mav be induced in the 
stomach and intestines, and slowly progress for years, 
and finally terminate in death, without ever being sus- 
pected by the subject, or affording such symptoms as 
lead to a detection of the evil by the physician. 

611. But the stomach does not suffer alone in its 
irritations and diseases. All irritations disturb the 
functions of the stomach, and more or less impair the 
quality of the chyme, and this leads ultimately to a 
deterioration of all the fluids and solids of the body. 
Besides, in all those irritations which affect the gen- 
eral condition of the stomach, the heart, lungs, liver, 
and all the other organs of the system sympathize 
(297, 298), and by this sympathetic irritation their 
functions are also disturbed and impaired. And if, 
in consequence of hereditary peculiarities, or some 
other cause, the lungs, liver, or any other organ, is 
particularly predisposed to disease, these sympathetic 
irritations always tend to develope it; and when devel- 



oped, the local disease either reacts upon the stomach, 
and becomes a source of continual irritation to that 
organ, or serves as a kind of outlet or concentrating 
point, by which the gastric irritations are relieved, 
and tne stomach sustained in health at the expense 
of the diseased part, which suffers from every error 
of diet, from every gastric irritation however induced. 
Thus, continued ^stric irritation often produces spi. 
nal irritation, which reacts with tremendous energy 
on the stomach, in some instances completelv destroy- 
ing its functional power; and on the other nand, dis- 
ease may be induced in the lun^, liver, and other 
organs and parts, by gastric irritation, and carried 
forward to the destruction of the affected part, and to 
the extinction of life, continually exasperated by the 
originating cause, while the stomach itself seems all 
the while to be in excellent health, and the unfortu- 
nate sufferer is confident that nothing which he eats 
or drinks, or swallows as medicine, does him any in- 
jury, because * its sits well on his stomach.* In this 
manner, every organ and part of the human body in 
its turn may fall a sacrifice to the abuses and irrita- 
tions of the alimentary canal; and, with very few 
exceptions, fevers of every type, and acute and chro- 
nic disease of every form, may spring from the same 
source. With what propriety, then, did the Psalmist 
exclaim, ' I am fearfully and wonderfully made.* 


Nature of the soul— Immortality of man— Connexion of the soul 
with organized matter — The laws that govern it — Brain the seat 
of intellectual and moral fkculties— Views of Gall and Spurz- 
heim concerning the organs of the brain and the mental and 
moral faculties — Elements of intellectual and moral character 
in man, and the diversities of manifestations— These phrenolo- 
gists attribute to cerebral organization — The cerebral organs 
enumerated, described, and located— Temperament and phy- 
siognomy—Combinations of faculties in forming character — 
Plurality of cerebral organs proved by the mental relief f^om a 
change of subjects— By monomania — The laws of mind in san- 
ity and insanity — Its organic instruments— Special senses — 
Sight the source of imagery— The philosophy of vision— Mental 
perception — Mental conception — Reflection — Perceptions of the 
difibrent senses not reproduced with equal ease and vividness — 
Associations of perception and reflection — Associations of reflec- 
tion, conception, and propensities and sentiments — Mental 
effects of intoxicating liquors in religion, etc.— The Mind can- 
not perceive two distinct objects at once, nor perceive and con- 
ceive distinctly at the same time — Perfect sleep — Dreams, how 
produced and affected— Conceptions of the poet, etc. — Distinct 
conception takes away the power of perception at the same 
instant— Dreams, and conceptions while awake, realities to the 
mind while they last— Nervou3 irritation, how it produces mania 
— All the feelings and affections by whatever produced enter 
into the mental operations, and affbct the Judgment — hence 
according to the feeling, so the conclusions — As we feel on a 
svbject, so is its importance to our mind— Wine, music, beauty ; 
their effects — Strict mental sanity deflned— Insanity, what, and 
how caused- Mind always true to its laws— How fkr this favors 

?hrenology — Does local disease of the brain cause insanity f — 
nsanity fh>m irritation in the domain of organic life — Phre- 
nology makes the brain too exclusive — Intellectual and Moral 
Physiology the true science. 

512. We have seen that all matter, if not essen. 
tially^ sfngle element f 72, 87), consists of a very few 
primordial substances (73), and that the same matter 
IS common to all material forms (49), both inorganic 
and organic (112, 118); that the various forms of 
matter are }>roduced by the different arrangements of 
the same primordial atoms (80, 106); and, therefore, 
that the nature a thing depends in no degree on the 
matter of which it is formed, but entirely on the con- 
stitutional laws of arrangement (140): and these laws, 
it is contended, do not arise from the intrinsic proper- 
ties of matter (83), but are imparted to it, by an om- 
nipotent and infinitely wise and benevolent Creator 
(89); and from the constitutional nature of things 
thus established, all their properties and powers arise 
(140). We have seen also, that the most primitive 
laws and properties imparted to matter, are those 
which belong to inorganic forms (100), and that the 

laws and affinities of inorganic matter are directly 
adverse to the laws and affinities peculiar to organic 
matter (107); and consequently the arrangement of 
matter in the formation of organized bodies is the 
effect of the operation of constitutional laws which sus. 
pend and overcome the laws and affinities of inorganic 
matter (110): and hence the constitutional laws and 
properties peculiar to living organized bodies cannot 
arise from inorganic matter, nor result from the oper. 
ations of any of the laws or affinities of inorganic 
matter ; and therefore the constitutional laws and 
properties peculiar to organized bodies, were super, 
induced and established in the permanent econonty 
of organic vitality, by an omnipotent and infinitely 
wise and benevolent Creator (89). 

513. The same train of reasoning is equally appli* 
cable to the differences existing between v^fetable and 
animal forms of matter (114), and the properties and 
powers peculiar to animal bodies ; and also to the dif- 
ferences existing between the cellular, muscular, and 
nervous tissues of animal bodies, and the properties 
and powers peculiar to each of these tissues (312). 

514. It is not, therefore, in the nature of things, 
possible that vitality nor any of the properties pecu* 
liar to the living tissues should spring from the intrin- 
sic properties or powers of matter (108), nor from any 
organic arrangement of matter; but, on the contrary, 
the organic arrangement of matter is always neces* 
sarily the effect of vital action ; and the properties 
and powers with which each tissue is endowed as a 
living substance, arise, not from the arranged matter 
of the tissue, but from the vitality residing in the tis- 
sue. The vitality of the different tissues differs in 
degree, and there is reason to believe that the vitality 
of the muscular tissue is of a higher order than that 
of the cellular . tissue, and that the vitality of the 
nervous tissue is of a higher order than that of the 
muscular, and that the vitality of some parts of the 
nervous tissue is of a higher order than that of other 
parts ; and it is possible that the vitality of some por- 
tions of the brain is of a higher order than that of 

515. But when we speak of the laws and properties 
of matter, what do we mean (88) ? We talk of the 
law of gravity ; and so far as the size, weight, distance, 
velocity, etc., of attracting bodies are concerned, we 
can reason with mathematical accuracy and precision; 
but with all this extent and accuracy of knowledge in 
regard to the fixed order of the phenomena of g^vity, 
what do we know of the essence of that power which 
we call the attraction of gravitation ? Absolutely no- 
thing ! The chemist also speaks of the molecular affini- 
ties of matter, and the laws which govern the combina- 
tions of his experimental elements; yet he is totally- 
ignorant of that power or property which he calls 
affinity, and the fixed order of whose phenomena he 
calls law. The astronomer and the chemist, there- 
fore, cannot, from their knowledge of the essences of 
things, either affirm or deny that the power which prom 
duces all the physiceU and chemical phenomena offmatter 
is the omnijtc and omnipotent spirit of God, 

516. We use the word law then, in regard to matter, 
as an abstract term, to signify a fixed order of phe- 
nomena that are produced by a power of which we are 
entirely ignorant. Hence all evidences of design and 
of final causes go, without any drawing back, to prove 
either that an omnipotent and intelligent First Canse 
continually exerts a direct and controlling influence 
on matter, or that the essential nature of each form of 
matter (140) which governs all the phenomena of its 
particular form, and which is the sulratratum of all the 
properties and powers of its form, was originally es- 
tablished, and is continually sustained, in a perma- 
nent constitutional economy by the Creator. 

517. While, therefore, we cannot, from our know- 
ledge of things, affirm what the essence of life is (41), 
we know as certainly as we know anything concon- 



ing matter, that it could not spring from any of the 
properties or powers of inorganic matter, and that its 
relation to the organization of matter is of necessity 
in the nature of things, and has ever been since the 
first establishment of the rital economy in connexion 
with organized matter, that of a cause and not of an 
effect (108). Hence it may be boldly affirmed, that 
no man possesses knowledge which justifies the asser. 
tion, that the power which governs the organization 
of the nervous system of animal bodies, and consti- 
tutes the substratum of all its properties and powers, 
is not a substance essentially different from matter. 
Nor does any man know anything contrary to the 
idea that this substance may differ in different orders 
of animals. 

^ 518. Purely as physiologists, then, with all the 
light of science around us, we can, with at least as 
much philosophical propriety, affirm that the substra- 
tum of the sensorial power of the human brain (514) is 
a spiritual substance^ as any one can affirm the con- 
trary ; and the truth of our affirmation is infinitely 
more probable than it is that mind and moral feeling 
are results of organized matter. It is frankly con- 
fessed, however, that as mere physiologists, we can 
offer no evidence of the future existence of man. This, 
of necessity, in the nature of things, is purely a doc 
trine of revelation. As metaphysicians we may rea- 
son very forcibly to such a conclusion from what we 
regard as moral evidence and general analogy, and 
froon the intellectual and moral fitness of man for 
such an existence ; but, apart from the sacred Scrip. 
tures, we have no decisive proof that man will exist 
in a future state. But while it is true that physiology 
affords no evidence of man*s future existence, it is 
also true that it affords no proof to the contrary ; and 
the important fact that all the bearings of the Gospel 
of Jesus Christ, on the present state of human exist- 
ence, accord most perfectly in all respects with the 
physiological laws of our nature, almost amounts to a 
demonstration that the doctrines of that Gospel con- 
cerning our future existence are true (603). 

619. Since, therefore, physiology cannot prove that 
the sensorial power of the human brain is a property 
of matter, nor that it is a result of the peculiar organ- 
ization of the matter of the brain, and since all that 
we know of the laws and properties of matter is ad- 
verse to such a notion ; and since the Gospel of Jesus 
Christ, which comes to us with the strongest possible 
evidence of its divine authenticity, explicitly affirms 
the existence of a soul in man which shall exist beyond 
the grave eternally, it may be boldly affirmed that the 
hnman soul is an immaterial substance, and that it 
constitutes the substcatum of the sensorial power of 
the human brain ; a^d no man can show from the 
demonstrations or facte of science, that this opinion 
18 not strictly philosophical, and the most probable of 

620. It is entirely certain, however, that, whatever 
be the substratum of the sensorial power of the 
human brain, it/esides in and acts through the organ- 
ized matter of the nervous substance, during our pre- 
sent stale of existence, precisely the same as if it were 
merely a property (^ that vitalized matter ; and all its 
powers and manifestatioiis are subject to precisely the 
same laws as govern the powers and manifestations 
of vitality. This truth is of immense importance to 
every human being. Indeed, it lies at the very 
foundation of inteUiBotual and moral and religious 
philosophy, and is of vital interest to human happi- 
ness in every point of view. Instead of neglecting it, 
therefore, as a matter unworthy of our consideration, 
or of r^farding it as of secondary importance, or of 
combatmg it with vain assertions and denunciations 
as heretiod, we should diligently study to understand 
it, in all its depth and breadth and bearings and 

'621. Should it be asserted that this doctrine proves 

the immortality of the lower orders of animals equally 
with that of man, I reply — 1, that, according to the 
views which I have advanced, there may be an essen- 
tial difference between the substratum of the sensorial 
power of the nervous system of the lower animals, 
and that of the sensorial power in the human brain 
(517) ; 2, that the immortality of man, or his future 
existence, does not depend on the nature of his soul, 
but on the will and power of the Creator. The 
human soul, equally with the human body, depends 
on God for its existence ; and if we exist in a future 
state, it will be purely becavse God wills it, and not 
because the human soul is self-existent. Therefore, 
unless it can be shown that God has revealed the doc- 
trine of the immortality of the lower animals as ex- 
plicitly and fully as he has that of man, then my rea- 
soning does not in any manner go to prove the im- 
mortality of the lower orders of animals. But it is not 
the business of physiology to prove the immortality 
of the human soul, and it is not possible for it to 
prove the contrary. 

522. In regard to the particular seat of the human 
soul, different opinions have prevailed at different 
periods of time, and amongst different nations ; but 
it would neither be interesting nor instructing to re- 
view, on the present occasion, the various theories 
and speculations which have been advanced on this 
subject. The human brain is unquestionably the more 
immediate and special organism of the mental and 
moral powers ; and the grand question before the world 
at present is, whether the mind acts in and through 
the brain, as a single organ, or as a system of organs. 
This question has, indeed, been agitated to some ex- 
tent, ever since the time of Aristotle, and probably ever 
since the human mind first began to speculate on the 
relations between mind and body ; but it has been 
made a more prominent object of contemplation and 
inquiry in our own day, by the theory which has 
been advanced by Dr. Gall, and advocated and im- 
proved by Dr. Spurzheim and others (274, 279). 

523. Without stopping to review the progress of 
this theory from its origin to the present moment, I 
shall proceed to present a brief abstract of it, as it 
last came from the hands of Dr. Spurzheim. Accord- 
ing to this theory, as I have already stated (267, 268), 
the brain is composed of diverging and converging 
fibres of medullary substance, which are so arranged 
as to form in connexion with the pulpy or gray mat- 
ter of the brain, a system of duplex organs ; and eadh 
pair of these organs are a specific and distinct faculty 

524. The organs are divided, according to their 
functional character, into Propensities, Sentiments, 
and Intellectual Faculties. The Propensities aiB 
situated in the lower and back part of the skull, and 
are all common to man and the lower animals. The 
Sentiments occupy the upper portion of the skull, and 
are subdivided into those which are common to man 
and the lower animals, and those which are peculiar 
to man. The Intellectual Faculties belong to the 
fore part of the skull, or the forehead, and are sub- 
divided into perceptive and reflective faculties. 

525. This theory daims to be purely inductive, and 
to be founded on the correspondence between the)6on- 
formation of the brain, as evinced by the shape of 
the Ikull, and the mental and moral character ; and 
is called Phrenology, or the doctrine of the mind. 

526. It is a matter of common knowledge, that the 
greatest diversity of propensity, sentiment, and habits 
of thinking and o£ acting, are continually manifested 
in society, by different individuals ; and that this 
diversity may be traced through all stages of civiliza- 
tion and all periods of life, and often exists in a very 
remarkable degree even in small families. Some indi- 
viduals have an intense, instinctive love of life, and 
always contemplate death, or the extinction of life, 
with the deepest dread and even horror ; and this. 



too, without any regard to the pain of dyinff : while 
others HeJdom think of death, and have so little regard 
for life, that, were it not for their dread of the pain 
of dying, or of what may follow the death of the 
body, wey would, on slight occasions of disappoint- 
ment and vexation, throw life away. Some individuals 
are habitually given to the excesses of the table, and 
regard the indulgences of the palate as the highest 
and almost exclusive enjoyments of life ; indeed they 
often seem not to have the power to refrain from 
these indulgences, even when they know that disease 
and suffering must inevitably be the consequences of 
their yielding ; while others seem to eat and drink 
from a mere sense of duty to sustain the body, and 
never run into excesses. Some are extremely tender 
and gentle and merciful in all their actions, and are 
habitually careful to destroy nothing that can be of 
use to themselves or to any one ; while others, even 
from early childhood, evince a disposition to destroy 
almost everything they can lay their hands on, and 
delight in killing flies and other animals, and often 
become murderers of their own species. Some mani- 
fest an eager desire to enter into wedlock as early in 
life as possible, while others coldly prefer celibacy, 
and spend their life, from choice, in single blessed- 
ness. Some discover the greatest fondness for little 
children, and seem to prefer their society to any 
other. In some mothers the maternal feeling is 
supreme, and all the energies of their soul seem to 
yearn over their own sweet babes ; by day and by 
night, in health and in sickness, in prosperity and 
adversity, in honor and ignominy, they cling to them 
and hang over them in maternal devotedness, and 
are never weary of supplying their wants and admin- 
istering to their comforts. As the bosom of waters 
over which *the viewless winds' flap their hasty 
wings, so is the face of such a mother when her child- 
ren are acting or suffering before her ; every emotion 
which they manifest, and almost every movement 
which they make, ripple her countenance into ex- 
pressions of pleasurable or painful sympathy. Nor 
are her sympathies confined to her own children; 
she has always a smile for the playfulness of other 
babes, and a tear for their sufferings. Such mothers, 
even in the midst of penury and privation, consider 
their children their greatest earthly blessings, and 
never regard theni as burdens under any circum- 
stances. Others have the greatest aversion to little 
children, and can never bear their presence but with 
disquietude and annoyance. If such are mothers, 
they perform the maternal duties in a cold and hearts 
less manner, and are continually complaining of the 
toil and vexation which their children cause them, 
and are frequently heard to say how much better off 
they should be without children. Such mothers, in 
whom there is a want of the proper restraint of moral 
sentiment or of education, will abandon, and in some 
cases even destroy, their own babes. Some persons 
are extremely fond of society, and are strongly in- 
clined to form the attachments of friendship, and to 
become attached to particular things which they are 
accustomed to; while others seem to be isolated 
beings, shut up within themselves, and having no 
sympathies either for men or things. Some are pow. 
erfully attached to their home, and native place, and 
country, and are zealous and devoted patriots ; while 
others are equally at home in all places, and have no 
love for any country. Some are peaceable and meek, 
and timid and cowardly ; while others are bold and 
full of courage, and perhaps contentious and turbulent 
and quarrelsome, and always ready to fight on the 
slightest provocation. Some are excessively open and 
frank and communicative, blab every thing they know 
and hear and think, and never can keep a secret, nor 
practice any concealment nor hypocrisy ; they seem 
indeed not to be able to conceal their sentiments, even 
when they know th^r own welfare requires iti while 

others are always secret even in regard to trifles, and 
wrap everything in concealment and mystery ; they 
never speak without first considering what they are 
going to say, and whether it can in any manner be 
turned to their disadvantage; they seldom give a 
prompt and direct answer to an interrogation, but 
reply in an indirect, ambiguous, or evasive manner, 
and are frequently sly, crafty, hypocritical, and knav- 
ish, and given to falsehood. Some are excessively 
prodigal and improvident, and have no disposition to 
acquire anything ; while others have a strong desire 
to possess every&ing they see, and are prompted to 
the most diligent and indefatigable efforts to acquire 
g^eat possessions, and perhaps are extremel;^ parsi- 
monious and covetous and avaricious ; and in some 
cases the propensity is so great that it leads to habit- 
ual theft. Some seem to possess no aptitude to con- 
struct even the simplest kinds of machinery ; while 
others evince an irresistible propensity to be engaged 
in soitle kind of mechanical employment, and with 
astonishing aptitude soon become masters of the most 
difficult mechanical arts, inventing and constructing 
the most complex pieces of mechanism as if the whole 
were a result of peculiar intuition. 

527- Some individuals are extremely incautious 
and rash, while others are very circumspect and ex- 
cessively cautious. Some are perfectly reckless of 
the opinions of others, and have no desire for appro- 
bation and distinction; while others are extremely 
sensitive to the slightest expression of disapprobation, 
and feel a continual and powerful desire to be the 
objects of attention and admiration and praise, and 
have a deep and fervent longing for renown and 
glory, and immortality of fame. Some have little 
self-confidence and self-respect, and always throw 
themselves upon a level with those in whose company 
they may happen to be; while others feel a great 
degree of self-confidence, self-esteem, and self-import- 
ance ; they speak as if they thought themselves the 
very oracles of wisdom, are exceedingly reserved and 
dignified, and perhaps consequential in their man- 
ners, and often haughty and contumelious. Some 
seem to live only for self; all their actions and all 
their plans of life begin and end in self. They feel 
no interest in the common welfare of mankind, and 
no sympathy for any cause which aims at the im- 
provement of the condition of their species ; while 
others appear to lose self in their extended feelings 
and plans and efforts of benevolence and philanthropy. 
Their feelings and their thoughts are continusdly 
occupied in devising and maturing and carrying into 
operation schemes of benevolence by which mankind 
may be made better and happier. ' They are kind- 
hearted, and affectionate and merciful to every human 
being, and indeed to every thing that feels. 

528. Some feel great respect for superiors, and 
great deference for traditionary authority, and the 
most solemn reverence for the Supreme Being ; while 
others seem to want these feelings entirely. Some 
possess great firmness and decision and perseverance 
and resoluteness and stubbornness and obstinacy, 
and love to exercise authority and to command; 
while others are unstable and yielding and submissive 
and obedient. Some are exceedingly conscientious 
in every thing they do, say, and think, and alwa^rs 
desire to be strictly just in all their dealings ; and if 
they think they have wronged or in any manner done 
the slightest injustice to any one, they cannot rest 
till they have set the matter right; while others 
seem almost totally destitute of conscientiousness, and 
even pride themselves in their dishonesty and fraud 
and knavery, and boast of their succ^s in over-reach- 
ing, deception, and cheating. Some are full of hope 
and expectation of good things to come ; while others 
are inclined to despondency and despair. Some are 
extremely credulous, and strongly inclined to believe 
every thing that is associated with mystery and with 



tkn marvellous and lupernatural ; while others are 
Bpeptical in every thing, wholly reject the marvellous, 
deny the existence of a God, and almost doubt their 
owjQ existence. Some are exceedingly ardent and 
enthusiastic, and have the most vivid and vigorous 
imaginations, and behold every thing with poetic 
yision and feelings ; and to them the earth is a para- 
dise or a purgatory, and the human species are angels 
or devils : while others are always the same, unvary. 
ingy cold, matter-of-fact beings, who estimate things 
by weight and measure, and regard the visions of the 
poet as the hallucinations of a diseased brain, and his 
enthusiasm as the excitement of insanity. Some are 
always full of mirth, and facetiousness, and wit, and 
jest, and drollery, and satire ; while others are habi- 
tually sober, and serious, and saturnine. Some have 
a powerful inclination and wonderful aptitude to imi- 
tate and mimic the actions, gestures, voice, expres- 
sions, etc., of men and animals ; while others have 
neither the disposition nor the power to imitate any 

529. Some are remarkable for noticing with great 
minuteness and accuracy individual persons and 
things, and all the peculiar habits, qualities, and 
appearances of individuals ; while others pay no atten- 
tion to such things. Some have a great aptitude to 
notice and judge of forms, figures, and features, and 
remember countenances with great accuracy ; while 
others are very deficient in this power. Some are 
remarkable for the power of measuring distance, size, 
etc, by the eye. Others will judge of weight with 
astonishing accuracy; and others have the nicest 
perception of colors in all the delicate varieties of 
hues and tints ; while others seem almost totally des- 
titute of these powers. Some persons are remarkable 
for their power of perceiving and remembering the 
relative situations and localities of external things, 
and all the features of a landscape, and are exceed- 
ingly fond of travelling and of seeing new places and 
countries ; while others are the very opposite of this 
in all respects. Some are very notable for their great 
precision and systematic arrangement and order in 
all they do and say ; everything belonging to them is 
kept in the most precise order : while others are as 
notably careless and slovenly, and destitute of method 
and order. Some are remarkable for their power of 
numeration, and will run through processes and arrive 
at results in numbers with a promptitude and accu- 
racy which seem absolutely supernatural ; while 
others are scarcely able to carry through a simple 
process in arithmetic. Some are astonishingly accu- 
rate and minute in their knowledge of particular 
events, and seem to have the whole history of the 
world in detail stereotyped upon their brains ; while 
others are utterly incapable of remembering particular 
events, and can only retain general impressions and 
fundamental principles. Some will remember dates 
and the successive periods of events with wonderful 
aoeuracy ; while others tind it impossible, even with 
the utmost labor, to impress dates upon their memory. 
Some seem natural instruments of music, and have 
only to open their mouths and the air issues from 
their lungs in the most enchanting tones and strains 
of melody ; while others seem incapable of learning a 
tune, or even of distinguishing one tone from another. 
Soma have a wonderful affluence and facility of lan- 
guage ; they commit language to memory, and learn 
new languages with great ease, and are never at a 
loss for words ; they remember names with astonish- 
ing accuracy, and in some instances they are capable 
of talking or speaking for hours with grammatical ac- 
curacy, and even with rhetorical richness of language, 
while at the same time they seem to be like mere 
band-organs, uttering well-ordered sounds without a 

690. Some are remarkable for their very acute and 
diaorimiaating power of comparison, while others are 

very deficient in this faculty. Some have an irresist- 
ible inclination and a wonderful power to search and 
find out the causes of things, and are always in pur. 
suit of first principles, and delight in philosophic in- 
vestigations, and are exceedingly fond of original 
pursuits and enterprises and discoveries ; while others 
are in all respects the very opposite of this, and pre- 
fer to trudge along the common beaten track of the 
world, taking things as they come, in the shape of 
separate facts and individuals, and never give them- 
selves a care or entertain a thought about causes and 
general principles and relations. 

531. Now, according to phrenology, the elements 
of all these differences and diversities are constitu- 
tionally innate, and depend entirely on cerebral orga- 
ization, development, and activity ; each of the pro- 
pensities and sentiments and intellectual faculties 
being prominent and vigorous, or obscure and feeble, 
according to the size and activity of that particular 
part of the brain which is its special organ ; and the 
relative size of the several organs being evinced by 
the general proportions of the head, and the particular 
elevations or depressions of the outer surface of the 

532. By carefully examining the heads of a great 
number of living, and the skulls of many dead per- 
sons and animals, and comparing their general and 
particular proportions with the mental and moral 
character and peculiar propensities and habits of the 
individual, Dr. Gall succeeded, as he believed, in 
ascertaining the particular location of twenty-seven 
pairs of the cerebral organs (275). Following the 
same inductive method, as he affirms, Dr. Spurzheim 
has added several pairs to the number described by 
Dr. Gall, and has left us the description and location 
of thirty.five pairs of these organs, and has named 
two other pairs,* the localities of which are not yet 
fully ascertained (279). 

533. Thus then, according to this theory of Phre- 
nology, we are furnished with thirty-seven pairs of 
cerebral organs, which are the seats of all the animal 
instincts, and of all the moral and intellectual powers 
that we possess, and which are precisely adapted to 
the condition and wants of the body, and to the great 
purposes of individual and social life. £ach pair of 
organs perform a separate and distinct function ; and 
' the essential nature of each primary power,' says 
Dr. Spurzheim, ' is one and invariable, and no organ 
can produce two species of tendencies.' 


534. If we enumerate the cerebral organs in the 
most philosophical order (526), we shall begin with — 

1st, Vitativeness, or the organ of the instinctive desire 
of life. This is supposed to be situated at the base of 

* VitativeneBS and Alimentivenesa. 



the brain, where the middle and po&terior lobes meet. 
To sustain life, we have — 2d, the organ of Alimentive' 
nesi, or the instinct that prompts us to take food. 
This is supposed to be situated before the ear, imme- 
diately under acquisitiveness and before destructive- 
ness. To supply the alimentary and other wants of 
the individual, to demolish and destroy whatever is 
hurtfid to the body or endangers its existence and 
well-being, or whatever the good of the individual 
requires, we have — 3d, the organ of Destructivenessy 
or the propensity to destroy ; or more properly, the 
propensity to satisfy or execute the demands of the 

other instincts, at all events, even though it require 
the demolition and destruction of other things, or 
whatever stands in the way, or opposes ; and, there- 
fore, when unduly developed and active, or greatly 
depraved by bad education and habits, and unbalanced 
by counteracting moral organs, it produces cruelty, 
ferociousness, and murder. This is situated imme- 
diately above the ear. To secure the multiplication 
and perpetuity of the species, we have — 4th, tne organ 
o{ Amaiiveness, which consists of the two lobes of the 
little brain, situated at the base of the skull, behind, 
over the back of the neck. For the protection and 
cherishing of offspring, we have — 5th, the organ of 
PhiloprogenitivenesSf or the instinctive love of children, 

— the maternal feeling. This is situated at the back 
part of the head immediately above amativeness. To 
secure the connexions and institutions of domestic 
and social life, we have — 6th, the organ of Adhesive- 
nesSf or the instinctive propensity to form attachments 
to things and friendships with persons. This is situ- 
ated at the side of philoprogenitiveness, and a little 
above. And to secure the more extended interests of 
domestic and social life, we have — 7th, the organ of 
Inhabitivenss, or the instinctive love of home, of native 

place, and country, giving rise to patriotism, etc. 
This is situated immediately above philoprogenitive- 
ness. For the defence of self and family and home 
and country, we have — 8th, the organ of Combative^ 
nessy or instinctiye courage, or the propensity to over- 
come obstructions and difficulties, to resist opposition, 
repel attacks, etc. ; and when excessive and unbal- 
anced, produces contentiousness, quarrelsomeness, etc. 
This is situated between philoprogenitiveness and the 
ear. Still further to secure the interests of self and 
family and country, and to counteract and defeat 
superior force by management or stratagem, we have 
— 9th, the organ of SecretivenesSy or the instihctive 
propensity to secrecy, concealmeht, slyness, cunning, 
craftiness, etc. This is situated a little above des- 
tructiveness. To provide for the wants of self and 
family, and to sustain the institutions of society, we 
have — iOth, the organ of Acquisitiveness y or the in- 
stinctive propensity to acquire property, or whatever 
ma^ be useful to us, or minister to our wants, the 
desire to possess, disposition to be provident, etc. ; 
and when excessive and unbalanced, produces parsi- 
mony, covetousness, avarice, and theft. This is situ- 
ated before and a little above secretiveness. For the 
protection and comfort and convenience of self and 
family and society, we have — 11th, the organ of Con^ 
structivenessy which leads to the building of houses, 
the construction of all kinds of machinery, etc. This 
is situated at the temples above the cheek bones. 


535. To secure that circumspection and prudence 
and discreetness and caution which our condition and 
circumstances in life render necessary for individual 
and social welfare (527)> we have — 12th, the organ of 
Cautiousness, which is situated at the back comers of 
the head, above and a little behind the ears. To 
prompt us to seek the good-will and favorable opinion 
of others, and to incite us to the performance of those 
public and private deeds which serve the best inter, 
ests of society, and become the foundations of honor- 
able distinction and fame, we have — 13th, the orgam 
of Love of Approbation, or the instinctive desire for 
distinction, which in the excess leads to vanity and 
ambition and the restless strife for public applause 
and glory. This is situated between cautiousness 
and the crown. To secure a proper stability and 
dignity of deportment and character, and to prompt 
us to undertake those deeds and enterprises which 
we have the ability to perform, and which private and 
public good requires, we have — 14th, the organ of 
Self'Esteem, which in the excess leaids to personal 
pride, haughtiness, superciliousness, contumelious* 
ness, etc. This is situated at the crown of the h^ad. 
To secure that gentleness and affectionate conduct 
and kindness of demeanor and mercifulness, which 
are so essential to the happiness of domestic and 
social life, and those philanthropic efforts and enter, 
prises which the public good requires, we hare — 15th, 
the organ of Benevolence, which is situated at the top 
of the forehead, near where the hair commences. 


536. To secure that respect for the opinions of 
others, and especially for the aged, the experienced, 
and the wise, and that reverence for superiors, and 
for the authority of those that have lived before us ; 
and most of all, 'to secure that deep and solemn vene- 
ration for the Supreme Being, which the individual 
and social and civil good of man requires, we have-— 
16th, the organ of Reverence, which is situated at the 
top of the head, mid-way between the crown and the 
forehead. To give us fortitude, decision, and perse- 
verance of character, we have — 17th, the organ of 
Firmness, which in the excess degenerates into wilful- 
ness, stubbornness, obstinacy ; and becomes a desire 



to exercise authority and to command. This is situ- 
ated at the top of the head, next in front of self- 
esteem. To check our many selfish propensities, and 
to secure individual and civil integrity and righteous- 
ness, we have — 18th, the organ of Conscientiousness, 
or the instinctive disposition to do right, to be just. 
This is situated on the side of firmness, or between 
firmness and cautiousness. To sustain us under the 
numerous discouragements and continued disappoint- 
ments of life, and to support us even when the ' life 
of life is gone,* and nothing of this world, either in 
possession or in prospect, remains to cheer or com- 
fort us, we have — 19th, the organ of Hope, which 
leads us on from day to day, with expectations of 
good things to come; and when it can no longer 
cling to the promises of this world, it stretches for- 
ward and lays hold of the promises of a future state 
of being.^ This is situated by the side of veneration. 
To sustain the hope of life and peace and happiness 
beyond the grave, and to prompt us to look for those 
evidences which will afford us the belief of the exist- 
ence and continual care and benevolent purpose of 
the Supreme Being, we have — 20th, the organ of 
Marvellovsness, or instinctive disposition to ' look 
through nature up to nature^s God.' This is situated 
in front of hope. To exalt the mind * to all sublimer 
tUng^,' to afford us the most elevated conceptions of 
tnith and moral beauty and the perfectibility of 
things, and to stimulate us to the noblest and most 
honorable deeds, we have— 21 st, the organ oi Ideal'Uy, 
which is situated about mid-way between benevolence 
at the top of the forehead, and the ear. To break 
up the monotony of life, to give elasticity to our ener- 
gies, and variety to our emotions, and to increase the 
pleasures of our social intercourse, we have — 22d, the 
organ of Mirthfulness, or instinctive disposition to 
facetiousness, wit, pleasantry, drollery, satire, etc. 
This is situated at the corners of the forehead, in 
front of ideality. To enable us to represent our ideas 
of men and animals by signs, and tones, and gestures, 
and to acquire the necessary and the useful and the 
elegant arts of society, we hav&-^3d, the organ of 
ImitatUm, which is situated between mirthfulness and 

637. Of the Perceptive or Kkowino Faculties 
of the mind (629), we have— 24th, the organ of Indi- 
viduality, or instinctive disposition to notice objects 
in their individual capacities, habits, and peculiarities. 

This is situated between the eyebrows 25th. The 

organ of Configuration, or the instinctive disposition 
to notice figures, and power to reeoUect persons and 
forms seen before.--^6th. The organ of Size, or the 
instinctive disposition to notice size, measure 
distance, dimensions, etc. — 27th. The organ of 
Weight, or the faculty of judging of the weight 
of things, etc. — 28th. The organ of Coloring, or 
the faculty of nicely discriminating colors, hues, 
tints, etc.— 29th. The organ of LooalUg, or th« faculty 
which perceives and remembers tbe situations and 
relative localities of exttrnid objeeM, and leads to the 
love of travelling. — 30th. The organ of Order, or the 
power and inclination to perceive and observe order, 
and method, and precision of arrangement. These 
last six organs are situated in the range of the eye- 
brows, arching from the innei to the outer corners of 
the eyes. — Slst. The organ of Co/ou/a/ion, or the faculty 
of numeration and calculation in general. This is 
situated at the outer corner of the eyes, towards the 
ears. — 32d. The organ of Eventuality, or the faculty 
of acquiring a knowledge of events and occurrences, 
and of noticing and remembering every thing that 
happens, and which leads to historical knowledge. 
This is situated in the centre of the forehead, imme- 
diately above individuality.— 33d. The organ of Time, 
or the faculty which perceives and retains the succes- 
sion of events, remembers dates, etc. This is situ- 
ated on the outside of eventuality, towards the tem- 

ple. — 34th. The organ of Tune, or the faculty which 
perceives harmony and discord, and imparts the abi- 
lity to sing and to compose music. This is situated 
at the outer corner of the forehead, between wit and 
order. — 35th. The organ of Language, or the faculty 
of acquiring and retaining a knowledge of words and 
of languages, and the power of remembering the 
names of persons, things, places, etc. This is situated 
behind the eyes, and when large, causes the eyes to 
stand out prominently. 

638. The Reflective Faculties (530) consist 
of two pairs of organs. — 36th. The organ of Compari^ 
son, or the special power which compares the func- 
tions of all the other primitive faculties and discerns 
resemblances, analogies, identities, and differences. 
This is situated between eventuality and benevolence. 
— 37th. The organ of Causality, or the faculty which 
perceives the connexion between cause and effect, 
leads to the investigation of causes, and to the idea of 
the First Cause of all — God. This is situated on the 
outer side of comparison. 

539. The ancient doctrine of temperaments, and 
the somewhat more modern one of physiognomy, were 
at first disregarded or wholly repudiated by the phre- 
nologists, and the relative size of each organ and the 
general volume of brain were considered the principal 
or exclusive evidences of the power of the single and 
collective propensities, sentiments, and intellectual 
faculties. So that a large mass of brain, in a normal 
or proper state, was regarded as the sign of large 
powers ; and the intellect, sentimentality, or animal 
propensities of the individual were said to predomi- 
nate according as the cerebral mass lay more in the 
front or upper, or lower and back part of the skull. 
But it did not require very extensive observation to 
lead to the inductive conclusion that the capacitv of 
the forehead is not always the measure of the intellec- 
tual powers, even in a well-proportioned head. For, 
while it may be true as a general fact, according to 
the common impression of all ages, that the most ex. 
traordinary minds which have at different periods in 
the history of the human race impressed their unper- 
ishing energies upon the world, have had their seats 
in capacious foreheads, and been connected with large 
brains, yet we may everywhere meet with individuals 
with large heads and capacious foreheads, who possess 
no extraordinary powers of mind, but in some instan- 
ces are remarkable for their stupidity ; while, on the 
other hand, we every where meet with active and 
powerful minds in comparatively small heads, and 
rather low and narrow foreheads. To meet these 
difficulties, the doctrine of temperaments has been 
invoked in its fullest extent ; and finally, physio^- 
nomy has become completely associated with crani- 
ology in the present theory of phrenology. 

640. The size and general proportions of the head, 
the particular prominences of the skull, the tempera- 
ment and the physiognomy of the individual, are all, 
therefore, to be taken into consideration in judging of 
the intellectual and moral character of persons. Op 
in other words, both the size and activity or energy 
of the cerebral organs are to be considered ; and to 
ascertain the activity or energy the temperament is 
called in, and physiognomy is an important index of 
temperament, and of the mental and moral and ani- 
mal energies of the brain. 

641. No organ, however, is to be judged singly^ and 
absolutely, but relatively. As, for instance, if we 
find combativeness largely developed, we are not there- 
fore to conclude that the individual is a disputatious, 
contentious, quarrelsome fellow, who is continually 
in a brawl and fight ; but if we look still farther we 
may find that acquisitiveness, and cautiousness, and 
love of approbation, and benevolence, and conscien- 
tiousness, and ideality, and causality, are all likewise 
largely developed. In such a case the conflicting 
elements will qualify and regulate each other, so as 


out of the whole to form a harmonious unity of char- 
acter. Combativeness will carry the individual forward 
with an energy which will surmount every obstacle, 
and subdue every resistance and overcome every op- 
position, or perish in th^ attempt ; acquisitiveness 
will prompt him to pursue a course of gain ; love of 
approbation will prompt him to seek his gain in a 
manner by which he may distinguish himself and be 
Uie object of applause ; benevolence will lead him to 
seek his gain and glory in some enterprise of philan. 
thropv which aims at the general welfare of mankind ; 
causality will lead him to pursue his enterprise of gain 
and glory and philanthrophy in an original track and 
manner, and in a philosophic form ; ideality will give 
an elevated character to his enterprise, and enthusi- 
asm to his efforts ; conscientiousness will prompt him 
to be strictly just and righteous in all his principles 
and measures and operations and actions, by which 
he seeks to gratify his combativeness and acquisitive- 
ness and love of approbation and benevolence and 
causality and ideality ; and cautiousness will prompt 
him to be extremely careful to do nothing that will 
forfeit or jeopard his interest or his fame, or be in the 
least degree inconsistent with his principles of philan- 
thropy and strict righteousness, and cause him to 
examine ail the principles of his philosophy with the 
most rigid scrupulosity, and by the severest test of 
facts and experiments. With such an organization, 
therefore, the individual, if successful, would, like a 
Franklin, acquire wealth and fame in a manner which 
is not only consistent with, but highly conducive to, 
the general welfare of his species, and strictly com- 
patible with the purest and noblest private virtues. 

542. The phrenological theory of Dr. Gall, I have 
said (525), claims to be purely inductive ; and it is 
apparently supported by innumerable facts and coi;ici- 
dences, and is now too extensively received and too 
ably advocated and defended to be treated with ridicule 
or neglect. Every honest mind, therefore, which is 
thoroughly imbued with the spirit of truth, will en- 
deavor to examine it with candor and integrity, and 
neither seek to support nor to demolish it by any unfair 
means. If it be true, no one should wish to oppose 
it. If it be erroneous, no one should wish to defend, 
or to cover its errors. Yet if I mistake not, neither 
its opposers nor defenders have at all times manifested 
that candor and honesty which should always charac- 
terize our inquiries after truth. 

543. I am sure that I speak honestly when I say, 
that I have no prejudices against this theory, but am 
favorably inclined towards it ; yet candor obliges me 
to acknowledge that I am not so fully and entirely* 
convinced of its truth as some of its zealous adherents 
appear to be. Being early addicted to physiological 
investigation, and habituated to the closest observa- 
tion of the mental and moral manifestations of man 
in connexion with the physiological and pathological 
conditions of the body, I had arrived at, and was ac 
customed to teach, those doctrines of intellectual and 
moral physiology which I still continue to advance, 
long before I heard of Dr. Gall, or of his theory of phre- 
nology. I do not, however, intend to insinuate that 
anything like the views of Dr. Gall, in relation to the 
general shape and particular prominences of the skull, 
as connected with the mental and moral manifesta- 
tions of the individual, had ever entered my mind, 
except the common impression in regard to the capa- 
ciousness of the forehead, etc. ; nor do I claim to 
have conceived of the plurality of organs in the brain. 
X had, however, embraced and pubhcly advanced the 
opinion, that the nerves of special sense, and all the 
other nerves and parts within the cranium, and in- 
deed the whole cerebro-spinal system of nerves (232 — 
307), ^SLve a common centre of perception, at or near 
the top of the medulla oblongata (280) ; but this was 
then purely an hypothesis inferred from the phenome- 
na of mental and moral physiology. My attention had 

been directed almost entirely to the intellectuid and 
moral manifestations as affected by the physiological 
and pathological conditions of the body, and to the: 
analysis of the intellectual and moral powers as con- 
nected with the brain and nervous system as a whole; 
and in these pursuits I had arrived at the opinions 
which I still entertain in regard to intellectual and 
moral physiology, many of which are now claimed 
by writers on phrenology as belonging peculiarly to- 
that theory. 

544. There certainly appear to be many and strong; 
reasons for believing that the brain consists of a plu- 
rality of organs, and that these particular organs per. 
form special functions ; and also that there is a cor- 
respondence between the external shape of the skull' 
and the intellectual and moral character of the indi- 
vidual. Nevertheless it must be acknowledged thati 
none of these points has yet been conclusively de-^ 
monstrated, and therefore tney must still be regarded^ 
as at least in some measure problematical; 

545. One of the principal positions urged in support 
of this theory is, that when the mind has been severely 
applied to a particular subject till it becomes weary, 
if it be directed to another subject, it is instantly 
relieved, and feels comparatively fresh and vigorous. 
This, it is said, proves the plurality of organs in the 
brain, as the relief experienced arises from a change 
of the special organs in the mental operations ; or, m 
other words, that by turning the mind from one sub- 
ject to another, the weary organ is left to rest, and a 
fresh organ is caUed into exercise : for how, it is ask- 
ed, could relief be experienced by a change of sub- 
jects, if the brain acted as a single organ ? But this 
seems to suppose not only that there is a plurality of 
organs in the brain, but also that each individual 
organ possesses the capacity and power of carrying 
on a process of perception, reflection, reasoning, etc, 
independently of the other organs. Yet according to 
the general theory, the reflective faculties are more 
or less actively employed in all processes of reasoning, 
investigation, inquiry, etc. ; and, therefore, whatever 
may be the subject to which the mind is applied, the 
reflective faculties must be exercised in every act of 

546. If I understand the theory, the power of each 
special organ is a simple element of the mind, and not 
a complex power ; and all these elements together, 
constitute the one mind, and not a complex assemblage 
of minds : and in proportion as one or another of 
these elements enters more or less largely into the 
mental constitution, so is the mind qualified and 
characterized. If this statement is correct, then it is 
evidently unphilosophical, on phrenological premises, 
to suppose that one. organ or any number of organs 
can be so exclusively employed on one subject, as that 
a change of the subject will call into action a wholly 
new set of organs, and leave the weary ones to rest. 
For whether the subject be algebra or geography or 
chemistry or any other, some of the same faculties 
are always principally employed in every process of 
reasoning. Simple perception may be performed by 
a single organ as an element in the mental constitu- 
tion ; but when reflection, comparison, and reasoning 
take place, other organs must also be called into ex- 
ercise, and organs too which are always more or less 
concerned in every act of reasoning on every subject. 

547. Moreover the fact assumed in the case is very 
questionable. If two bushels of salt be placed on a 
man's shoulder, and he carry it till he becomes weary, 
and then if the salt be taken off, and two bushels of 
oats be placed upon the same shoulder, the man will 
feel greatly relieved, and it will almost seem to him 
that he has no load at all. And so in the labors of 
the mind ; if we apply our thoughts to a particular 
subject, till, to use common lanugage, the mind be- 
comes weary, and then turn our attention to some light 
and amusing subject, we certainly feel much relieved. 



But if the mind be severely employed on a particular 
subject till painful weariness is experienced, and then 
be applied with equal severity to another subject which 
requires an equal degree of mental power, so far shall 
we be from experiencing any relid*, that the weari- 
ness will continue and increase till it becomes intoler. 
able. ^ Sometimes the mind is greatly relieved by 
changing the question without changing the nature 
of the subject. As, for example: we may attempt 
the solution of a question in the science of numbers, 
and by some accident or mistake embarrass the men- 
tal associations in some of the processes, and continue 
to labor without success, till the mind, as we say, 
becomes extremely weary and confused or confound- 
ed ; and then we may turn immediately to another 
equally difficult question in the same science, and the 
mind will feel at once and very considerably Relieved, 
and will perhaps solve the question with very little 
difficulty, and then return to the former question, 
and solve that too, in less than one-fourth of the time 
that was devoted to it at first ; and finally quit ite 
labors with less sense of weariness than was felt when 
it turned to the second question. But does this 
prove that in changing the question we change the 
or«ins also ? — and that we have different organs for 
different problems in mathematics ? Evidently not ! 
On the whole, then, I conceive that this position, 
when properly examined, neither proves anything for 
nor against the theory of Dr. Gall. 

648. Another, and perhaps the most important, 
position advanced in support of Dr. Gall^s theory is, 
that we frequently see people totally insane on one 
subject, and perfectly sane on all others ; and it is 
contended that this fact can only be accounted for by 
admitting a plurality of cerebral organs, and that one 
of these organs is diseased. This position is strictly 
consistent with the philosophy of tne general theory, 
and may be correct ; and if so, is very conclusive : 
while on the other hand, if it can be proved to be 
incorrect, the general principles of the theory may 
nevertheless be true. 

549. The consideration of this position will neces- 
sarily lead us over the whole field of intellectual phy- 
siology. For, in order to ascertain what insanity is, 
we must first determine what sanity is; and this ren- 
ders it necessary that the elements and laws of mind 
should be clearly ascertained. In speaking of insanity, 
however, it is highly important that the meaning of 
the term should be accurately understood. Strictly 
speaking, the mind in itself is incapable of insanity. 
It is governed by certain general laws, which it always, 
and under all circumstances and conditions, obeys. 
Even in the worst cases of madness, the mind is true 
to its own laws ; and in obeying these laws, exhibits 
what we call insanity. 

550. "We have seen (620) that whatever be the sub- 
stratum of the sensorial power of the human brain, it 
resides in and acts through the organized matter of 
the nervous substance, during our present state of 
existence, precisely the same as if it were merely a 
property of that vitalized matter, and all its powers 
and manifestations are subject to precisely the same 
laws- as govern the powers and manifestations of 
vitality; and this is equally true whether the brain be 
a single organ or a system of organs. We have seen 
ahu> (242, 251, 262, 263, 264, 294, 296, 397, 398, 403^ 
409) that man possesses several orgrans of special sense, 
all of which convey their impressions to the cerebral 
centre of perception (280), from which they are re- 
flected to the mental organs. We have the special 
sense of touch (263), of taste, of smell, of hearing, and 
of sight. Hunger (247)9 ^^^ aU the other feelings or 
•enses by which the cerebral centre has cognizance of 
die specific wants of the vital economy, are likewise 
as truly special senses as taste^ smell, hearing, and 

551. The effect produced on the organs of these 

senses, and through them on the cerebral centre, by 
the action of appropriate stimuli, is what we call per- 
eepHon ; but neither the hemispheres of the brain (285) 
nor the lobes of the little brain (264), are essential to 
animal perception (259). Some portion, at least, of 
the hemispheres of the brain, however, is essential to 
intellectual perception. 

552. The sense of sight is the exclusive source of 
imagery to the mind. When the light is reflected 
from any object upon the retina of the eye. (252), cer- 
tain impressions are made upon the retina, which are 
perceived by the mind ; or, in other words, by which 
the mind has a perception of the object. 

553. There has been a good deal of speculation 
about the physiological and pyschological philosophy 
of vision (416), but the eye has too generally been 
treated as merely a mechanical organ, and considered 
as entirely passive in the function of vision ; and hence 
it has been compared to a camera obscura with its 
inverted image, etc. (416, 417)* So far as regards 
the mechanical and physical philosophy of vision, this 
is all well enough; but it does not explain the vital 
and mental function. It does not inform us how the 
animal sees the object. 

564. In one respect, at least, there is an essential 
and very important difference between the eye and 
the camera obscura: the optic nerve, with its expanded 
extremity forming the retina, is a living organ, endow- 
ed with a peculiar sensibility to all the properties of 
things which are perceived by the medium of light ; 
but this sensibility depends on the connexion of the 
optic nerve with the centre of animal perception, and 
on the healthy condition of the parts. And the per- 
ception being made by the organ in connexion with 
the animal centre, we do not actually see things in- 
verted, as has been generally supposed, because the 
mind does not perceive the inverted image formed upon 
the retina of the eye, as we perceive that of the camera 
obscura; but the image formed upon the retina of the- 
eye, instead of being perceived by the mind as an image 
or representation of an external object, constitutes what 
may be called the stimulusof visual perception, by which 
the external object itself is really seen. Or, in other 
words, the colors and all the other qualities of the image 
caused by the light reflected from an external object, are 
the real visual properties of the object, and are to the liv- 
ingorgan somany specific kinds of visual stimuli, giving 
to the parts on which they act the impressions which, 
being perceived by the animal centre (280), constitute 
the animal perception of the real external object ; and, 
therefore, the perception of the several parts of an 
external object is always made with reference to the 
direction of the rays of light which convey the stimuli, 
and consequently all external objects are seen in their 
natural and real position. 

. 666. When, for instance, the rays of light which 
are reflected from a person, animal, tree, or any other 
external object, fall upon the retina of the eye, an 
exact image oi the object is formed on the retina ; 
but as the rays of the light cross each other (fig. 48) 
before they reach the retina (416, 417), the image is 
inverted, and turned side for side ; but this image is 
not perceived by the mind as the image or represen*^ 
tation of the external object, but all the elements and 
qualities of the image act on the peculiar sensibility 
of the optic nerve, as specific and delicately modified 
stimuli ; or in other words, they are the real visual pro- 
perties of the external object, which act as the appro- 
priate stimuli on the retina of the optic nerve, in per- 
fect analogy with the action of gustatory, olfactory, 
and auditory stimuli on their appropriate organs. 

566. The peculiar sensibility of the gustatory nerve 
(294) in connexion with the animal centre of percep- 
tion, feels those properties of things which it is adap- 
ted to perceive, as sweet, sour, bitter, etc. ; and this 
IE the perception of taste. The peculiar sensibility 
of the olfactory nerve feds those properties of thingis 



which it is adapted to perceive, as the various odors, 
and this is the perception of smell. The peculiar 
sensibility of the auditory nerve feels those properties 
of things which it is adapted to perceive, as the various 
undulations or vibrations of air, etc., causing sound, 
and this is the perception of hearing. And in pre- 
cisely the same manner the peculiar sensibility of the 
optic nerve feels the visual properties of things, and 
this is the perception of sight. And thus the visual 
properties of external things as really and truly act 
upon the optic nerve, as the olfactory and gustatory 
properties of external things do upon the nerves of 
smell and taste. In each case the appropriate pro- 
perties are brought in contact with, and act upon, the 
nerve, as appropriate stimuli, producing specific im- 
pressions or sensations, which the mind perceives as 
the properties of the real things, and in perceiving 
these impressions or sensations, the mind always refers 
them to the things from which they are received, 
according to the constitutional laws of the particular 
function. And consequently the inverted image form, 
ed upon the retina, instead of being perceived as an 
image or representation of the external object, is felt 
as the visual properties of the real object itself, the 
same as its tangible properties are felt bv the organ 
of touch, the gustatory properties by tne organ of 
taste, etc. ; and therefore the impressions or sensa- 
tions produced by these properties, as the appro- 
priate stimuli of the organs, are instinctively and ne- 
cessarily referred to the real external object, whose 
visual properties act upon the organ, and in the direc- 
tion of the rays of light which convey the properties 
to the retina. Thus, though the visual properties of 
the top of an object (fig. 48) are thrown upon the 
bottom of the retina, yet from the constitutional laws 
of the function of vision, we instinctively and neces- 
sarily refer the impression or sensation to the top of 
the object, in the line of the rays of light by which 
the properties are conveyed to the retina, and conse- 
quently we actually see things just as they really are; 
unless we see them through distorting media, or 
through bodies which bend the rays of light, and 
change their colors before they reach the eye. 

657. Whether the optic nerve itself, or some other 
part, is the seat or receptacle of those impressions or 
sensations which constitute the mental ideas of the 
visual properties of external things, is not yet ascer. 
tained, and perhaps never will be ; but wherever the 
seat may be, it is certain that those impressions or 
sensations may be re-produced without the presence 
and actual perception of the external things by which 
they were first caused, and this reproduction is called 
mentcU conception, 

558. We have a visual perception of an external 
object when it is really before us and we actually see 
it, or whetiL its visual properties are actually thrown 
upon the retina of the eye ; and we have a visunl 
CONCEPTION of that object when, in its absence, #c 
reproduce the impression or sensation first caused by 
the action of the visual properties of the object on the 
retina ; or in other words, when the mind distinctly 
perceives the external object, without the refld visual 
function of the eye, or without actually seeing it : 
for the instant the impression or sensation is dis- 
tinctly reproduced, the mind instinctively and neces- 
sarily refers it, according to the laws of visual per- 
ception (554), to the external object by which it wa» 
first caused ; and thus, by perfect coneeptiony the ex- 
ternal object is made to stand as clearly and distinctly 
before the mind as it does in the real act oi perception^ 
And when our mental conception of external things 
is vivid, distinct, and complete, we call it ihagina- 


559. When a perception is made, it is instantly 
reflected to the intellectual faculties, and the reflected 
impression or sensation becomes a more abstract pro- 
perty of the mind, and is capable of being reproduced 

Bt any tune, without actual perception or real concep- 
lion (B^H), atid this is called reflection. 

seO- But our reflections always tend to produce 
conceptitvns, and are always the most dear and vigor- 
ous when our conception is the most vivid and dis- 
tinct ; and hence the writer or speaker who, when 
writing ar speaking, has the most vivid and accurate 
conception of the things of which he treats, always 
presents his subject most clearly and eloquently, and 
aiwQVJi produces the most powerful effect upon his 
rciaders or hearers, by presenting to their minds 
uiofit Vividly and distinctly the images of his own. 

5fil. Conception also greatly assists reflection by 
enabLing the mind to contemplate, examine, analyze, 
and compare things which have been perceived ; and, 
by ancertairiing the accidental and essential differ- 
ences, resemblances, and identities, to arrive at gene- 
ral conclusions and first principles, and thus elaborate 
the general theory of things. 

562, The power of recalling or reproducing the 
thoughts of reflection (559) in their regular associa- 
tmn^^J Is called memory ; and consequently memory, 
while it is a single attribute of the mind, is neverthe- 
lesj^, acf^ording to phrenology, of diversified power, 
and pertains to each individual organ of the brain j 
sn that we ttiay have a very good memory on onesub- 
jectj and <i very poor one on another, according to 
the relative activity and power of the individual 

563, Visual perception ^568), I have said (552), is 
the only source of that conception (558) which pre- 
sents imagery to the mind. Auditory perception ia 
also a source of mental conception, but to a more 
limited extent than that of vision ; and we are much 
more rarel y capable of reproducing the distinct im- 
pressions or sensations of auditory perception than we 
are thos* of vision. The reflected impressions or sen- 
sations (509) of auditory perceptions are, however, 
very easily reproduced, especially when the power is 
cuitivatefr, as in music. But, except in dreams and 
diaeatse, we never distinctly hear sounds by concep- 
tion. The perceptions of smell, taste, and touch, are 
aho rarely the sources of mental conception, except 
in dreams and disease.* 

564, The succession of our perceptions establi^es 
certain relations between the sensations of perception, 
and also between the thoughts of reflection (659), so 
that the reproduction either of a sensation of percep^^ 
tion or of a thought of reflection, naturally tends to 
the reproduction of others associated witn it ; and 
this h what is called the association of ideas, the 
law of assoc iation, etc. The perceptions of the ddffer- 
eni senses become associated in the same manner. 
Thus we look at a certain figure, and hear it called A, 
till we learn so completely to associate the visual and 
auditory perceptions in our thoughts of reflection, 
that they become inseparable, and indeed seem essen- 
tialiy oncj and the name becomes the mental abstract 
of the thing; and, except in cases of actual percep- 
tion or conception (558), all our thoughts are of this 
kind ; A species of a^elwaical a))straction or nominal 
representation in the mind, of ibings existing sepa- 
rately from the mind. Thus, we write and talk ra- 
pidly of trees, animals, men, etc., without having dis- 
tinct images of the things we write or speak of pre- 
sented to the mind. But, as I have said (560), reflec- 
tion alwayji tends to produce conception, and it rarely 
if ever becomes energetic and determinate, without 
producing some degree of conception, or reproducing 

• Mr. Jnn^es Hill, a respectable farmer, of West Cambridge, 
|iiKE.B>^ nQ>v a boat sixty years old, and in pretty good general 
beaUh. eiitirely lost the sense of smell ten years ago, and has 
»mctJled nn^tbinz since, not even the strongest and most pungent 
and cifetiSijve adors. Scill the sense of touch remains perfect in 
[he RDstrilg. Mr. Hill says he often dreams of smelling, and has 
& di.3 ticket and full conception of odors, especially the offensire. 
June 1, 18da. 



to some extent the primary sensations of perception 

565. The sensations of perception, both in their 
primary form, as reproduced in conception (668), and 
in the form of thoughts of reflection (659), are also 
intimately associated with our animal appetites and 
moral feelings ; so that the perception, the conception, 
and even the thought of certain things, will arouse 
certain appetites or propensities, or excite certain 
emotions or feelings ; and, on the other hand, the 
emotions or the appetites will call up the thoughts and 
conceptions. Thus, if we intently think of any kind 
of delicious fruit, or of any food of which we are fond, 
conception will soon present the fruit or food dis- 
tinctly to the mind*s eye ; and the animal appetite 
for it will soon be roused, and perhaps become even 
painfully importunate : and on the other hand, if the 
appetite be excited by the want of the vital economy, 
the thoughts and conceptions of something fitted to 
gratify the appetite will instantly be produced, and if 
the appetite be specific and determinate, the thing 
though t of and conceived will be specific. So, like- 
wise, if our perceptions of things are constantly at- 
tended with certain moral precepts, admonitions, or 
feelings, our conceptions of those things will always 
remind us of the associated sentiments, and generally, 
4#^ot always, reproduce the associated feelings ; and 
our thoughts of those things always tend to produce 
the conceptions (658), and thus excite the emotions. 
And, on the other hand, if the feeling^ be produced 
by a physiological or pathological condition of the 
body, the thoughts and conceptions are called up, and 
the mind contemplates the thing thought of, as the 
cause of the feeling (302—305). Thus, if an indivi- 
dual is devoutly and zealously religious, and always 
contemplates the favor of his God with pleasurable 
feeling^, ^hat physiological condition of his body 
which, in common language, is called a happy flow of 
animal spirits, will be sure to call up his religious 
thoughts and conceptions, and he will consider the 
feeling as entirely of a religious and spiritual chatu^. , 
ter and origin. So, likewise, if he is accustomed to 
the use of tea, coffee, wine, tobacco, opium, or any 
other alcoholic or narcotic or other stimulant, the 
pleasurable stimulation which he receives from his 
stimulant will, unless his attention is directly engaged 
in some other matter, call up his religious thoughts 
and conceptions, and he will attribute his happy 
frame to his religion ; and on the contrarjr, if from 
the pernicious effects of his stimulant on his nervous 
system, or from some other cause, a physiological 
depression results, a general feeling of distress or un- 
happiness will be induced, which will fill his mind 
with religious doubts and fears, and he will attribute 
his feeling entirely to those doubts and fears, or both 
the doubts and the feeling to the withdrawment of 
the fiivor of God. 

566. It is not possible for the mind to perceive two 
separate and distinct objects of thought at one and 
the same instant, nor is it possible for the mind to 
have a distinct perception and conception (568), at 
one and the same instant. When the mind is occu- 
pied with a distinct perception of things, no mental 
conception can take place ; and when it is occupied 
with a distinct conception, perception is wholly sus- 
pended. Thus, when we are completely absorbed in 
a reverie, or in that state in which the mind is per- 
fectly engrossed in the contemplation of its own con- 
ceptions, the functions of all our organs of sense are 
totally suspended, and we no more perceive any thing 
by sight, hearing, smell, taste, or touch, than if all 
our organs of sense were paralyzed. It is, indeed, a 
perfect dream. The instant we are conscious of a 
perception (651), the ideal presence vanishes, and the 
reverie is destroyed. The ability to retire within 
ourselves from tlie perception of every thing around 
us, and shut the mind up to its conceptions and re- 

flections, is called the power of abst&actiok, or in 
the language of phrenology, concentrativeness. But 
the constant action of the appropriate stimuli of vision, 
hearing, smell, etc., on the sensibilities of our organs 
while we are awake, renders it difficult for us to be- 
come as perfectly abstracted from the consciousness of 
surrounding things as when asleep, and therefore our 
mental conceptions are generally most vivid and dis- 
tinct, and the ideal presence most perfect, in our dreams, 
when our external senses are locked up in sleep. For 
dreams are nothing more than the more or less per- 
fect reproduction of the sensations of perception, with 
a varied extent of associated reflection. Whether 
thoughts of reflection (559) are first excited and lead 
to conception r668), or conception is first induced and 
excites thoughts of reflection in dreams, is not cer- 
tain. Perhaps sometimes one and sometimes the 

567. In perfect sleep, there is a total suspension of 
all the functional powers of the nerves of animal life 
(228, 229), and we neither dream nor are conscious 
of our existence. When we dream, therefore, our 
sleep is imperfect ; and it is rendered imperfect by 
some nervous irritation, or some physiological oppres- 
sion or depression in the body ; and this disturbing 
cause, whatever it be, is also the exciting cause of our 
dreams ; and the character of our dreams, as to plea- 
santness or unpleasantness, always corresponds with 
the nature and degree of the nervous irritation and 
the general condition of the nervous system, and 
especially the nerves of organic life (228). Most fre- 
quently, however, the exciting cause of dreams is 
some irritation in the digestive organs (297, 298, 299) ; 
but this is not always the case. 

568. Whether asleep or awake, then, when our 
conceptions (668) are complete or perfect, they are as 
much realities to the mind as our actual perceptions 
(651) ; and it is only when our conceptions have given 
place to actual perceptions, that we know that the 
conceptions are not real perceptions. Nothing is 
more real to the mind than dreams, while they last. 
We do not, we cannot know them from realities, un- 
til they cease to be, and we wake to reality, and find 
we have been dreaming. And this is strictly true of 
our day dreams or reveries, and of all our mental con- 
ceptions. The conceptions of the poet or the painter 
in what is called his moments of inspiration, are as 
real to his mind as his actual perceptions, and their 
effects upon his body are generally even more power- 
ful; and. when his conceptions are vivid, distinct, 
and compllete, it is impossible for him to know or to 
have the slightest suspicion, while they remain, that 
the ideal presence is not a reality. If, in the mo- 
ments of his high and powerful conceptions, we should 
see the poet, without impairing the spell of his soul 
in the least degree, and behold the intense meaning 
of his eye, and all the workings and expressions of 
his countenance, his violent gestures, his sudden 
starts, his hurried or suspended respiration, and hear 
him break forth in his soliloquies or in his addresses 
to the beings of his imagination, with tender, melting 
tones, or with terrible vehemence and fierce impetu- 
osity, we should certainly believe him to be a raving 
maniac, and probably, as others have done before us, 
shrink with shuddering dread from such fearful mani- 
festations of insanity. Yet in all this the poet^s mind 
operates in strict accordance with those general and 
fixed laws which govern every human mind, and is 
no more insane than the mind of the merchant is, 
when it is so completely engrossed in the conceptions 
of things that relate to his mercantile business, that 
he walks along the public street of the city without 
knowing whom he meets or what he passes. The 
only difference is, that the conceptions of the poet are 
o£ a more exciting character and produce a more ex- 
tensive and powerful effect on the whole nervous sys- 
tem, causing correspondent looks, gestures, etc. 



Besides, the general nervous excitability of those who 
are what we call poetic and other genuises, is much 
greater than ordinary ; and, in fact, this is the prin- 
cipal element of all genius. 

669. Perception and conception (558), I have said 
(566), cannot take place at one and the same instant ; 
and hence our conceptions are generally the most 
vivid and distinct and perfect in dreams, when the 
organs of perception are sealed up in sleep ; and hence, 
also, nervous people generally prefer to have a light 
in their bed-rooms during the night, so that they can 
see things distinctly when they are awake, and thus 
be able to prevent disagreeable conceptions, by actual 
perceptions. Upon the same principle, if an indivi- 
dual who is much afraid of dogs, is walking along the 
street in the day-time, and sees a large stone by the 
way, he does not mistake it for a dog, because he dis- 
tinctly perceives it to be a stone ; but if it be at night, 
when it is too dark for him to have a distinct percep- 
tion of the stone, the indistinct perception may in- 
stantly give place to a distinct and vivid conception of 
a dog, and while the conception lasts (568^, the dog 
will stand as distinctly before his mind as if it were 
an actual perception ; and the same effects will be pro- 
duced on his whole mind and body. 

570. No man is suspected of insanity because he 
dreams in his sleep ; and if one who is accustomed to 
do so, gets up in his dream, and with his eyes open, 
but without perceiving anv thing, walks about and 
acts and talks according to his conceptions, we still say 
he is dreaming ; but if he should remain in this state 
through the night and the following day, we should 
unhesitatingly pronounce it a case of insanity. Yet 
the mind would strictly observe the same laws that 
it does in ordinary dreams, and the same that govern 
it always when awake. 

671. The exciting cause of dreams, somnambulism, 
etc., I have said (567); is nervous irritation. When 
the system is perfectly healthy and undisturbed, sleep 
is death-like — a total and perfect suspension of all the 
function^ powers of the nerves of animal life (228), 
and of all consciousness of existence ; and the organs 
of external perception are, as it were, paralyzed to all 
external impressions, until the full purposes of ileep 
are effected, and the instinctive economy of organic 
life throws open the windows of the soul, and restores 
every sense to its appropriate organ. The nervous 
irritation which proiduces dreams may be carried to 
ftuch an extent of disease, as will cause such a con- 
stant succession or permanence of distinct and vivid 
conceptions, when we are awake, that our mind will 
be mostly or entirely engrossed with these conceptions, 
and almost wholly abstracted from actual percep- 
tions. The things conceived will be realities to the 
mind (568), and we shall think, feel, talk, and act, 
the same as if our conceptions were real perceptions ; 
and then, of course, we shall be called insane. If the 
nervous irritation runs so high as totally to engross 
the mind in its conceptions, and causes us to see all 
surrounding things as the objects of our conceptions, 
transforming our friends to savages, demons, etc., we 
shall be said to be totally insane, and perhaps raving 
maniacs, according to the degree of nervous irrita- 

572. The constant contemplation of things conceiv- 
ed, as realities, will soon establish new associations of 
thought and feelings (564, 565), and thus lay the 
foundation for permanent insanity, even when the 
general nervous irritation has much subsided. For 
intellectual habitudes of every kind are easily formed, 
and, when once established, are with great difficulty 
broken up, and especially those which are associated 
with our feelings and propensities. 

573. When the nervous irritation is less violent, 
and has been developed in connexion with certain 
qualifying circumstances and corresponding operations 
of the mind, as the loss of property, character, friends, 

etc., the morblA conceptions may be limited to a single 
subject, and then the case will be called monomania, 
or insanity on one subject, the mind being sound on 
all other subjects. 

574. Yet it is obvious that in all this, the mind 
observes the same laws that govern all human minds 
at all times (549). The soundest mind in the world 
regards its conceptions, while they continue, as real 
perceptions (568) ; and thinks, feels, and acts accord- 
Ingly ; and the insane mind does the same. 

575. Another general principle which I have al- 
ready alluded to, is of so much importance in the intel- 
lectual and moral philosophy of man, that it requires 
to be more extensively explained and illustrated. I 
have said (565j that the sensations of perception, both 
in their primary form, as reproduced by conception, 
and in the form of thoughts of reflection, are intimately 
associated with our feelings or emotions, so that the per. 
ception, the conception, and even the thought of certain 
things, will produce certain emotions ; and, on the 
other hand, certain feelings will excite certain thoughts 
and conceptions, by which the feelings or emotions 
will be very greatly increased. Thus, to repeat the 
former illustration (565), a zealously religious person 
who alwavs contemplates the favor of his God with 
pleasurable emotions, and the withdrawment of that 
favor with painful feelings, will have a pleasurable 
train of religious thoughts and conceptions called up, 
and hit hopes brightened and his faith strengthened, 
by that physiological condition of his body which we 
call a delightful flow of the animal spirits (305), 
whether produced by mental, moral, or physical sti- 
muli ; and he will consider the feeling as entirely of a 
religious and spiritual origin and character, and this 
feeling will be very greatly enhanced by the reaction 
of the thoughts and conceptions which it excites : and 
on the other hand, a physiological depression, by 
whatever cause produced, will be sure to call up in 
his mind a train of gloomy thoughts and conceptions* 
which will exceedingly augment his depression, and 
and he will be filled with religious doubts and fears ; 
his faith will become feeble, and his hopes will be 
darkened, and perhaps yield to despair, and he will 
attribute the whole of his distress to the doubts and 
fears of his mind, and these he will attribute to his 
convictions of his very great sinfulness, and the total 
withdrawment of the favor of his God. He will, at 
such times, review his past life with the deepest an- 
guish and remorse, and contemplate mapy former 
deeds as unpardonably sinful, which, in a healthier 
state of his nervous system, he regards in a very dif- 
ferent light ; and the darkness of his doubts, the 
depth of his despair, and the violence of his remorse, 
will always be proportionate to the morbid irritation 
and physiological depression of his nervous system. 
The unhappy Cowper affords a melancholy iliustra- 
tion of this doctrine. 

576. It is, then, a general law of the mind, which 
governs it in all states and conditions, that the impor- 
tance, in our estimation, of any subject which we con- 
template, or the force of any evidence which we exam- 
ine, is always equal to the degree of feeling or emotion 
connected with our thoughts, conceptions, and per- 
ceptions, on the subject, and consequently our reason- 
ings and conclusions correspond with our feelings. 
But, as we have seen (305), the mind cannot be con- 
scious of the difference between those feelings which 
arise from a peculiar physiological cond'.tion of the 
nervous system, and which cause our melancholy or 
pleasing thoughts and conceptions, and those feelings 
which are caused entirely by our thoughts, c<mcep- 
tions, and perceptions; and, therefore, when the mind 
acts according to its own consciousness, it always and 
necessarily judges that all our emotions or feelings 
connected with our thoughts, conceptions, and percep- 
tions, are entirely caused by those thoughts, concep- 
tions, and perceptions. And hence, unless we go out 



of ourselves, and judge of ourselves scientifically, and 
independently of our own consciousness, we necessa. 
rily attribute to the subject on which our mind is 
exercised, the influence or power by which all our 
intellectual operations and our feelings in regard to it 
are produced; and, therefore, we necessarily estimate 
the reality and importance of that subject, to us, by 
the degree of our feelings when contemplating it, 
whether those feelings are actually produced by the 
contemplation, by physical stimuli, or by morbid irri- 
tation and sympathy. Thus, when a person is in 
perfect health of body, he may hear of some expres- 
sions of disapprobation which have been made con- 
cerning himself, and regard them as a part of the 
common gossiping of society, and contemplate them 
with little or no emotion; but let the same person 
hear the same things when he is laboring under ex- 
treme nervous irritation and depression, and he will 
Contemplate them with great emotion, and all the 
morbid sensibilities of his nervous system, while they 
excessively increase the vividness of his conceptions 
(658), and the energy of his thoughts on the subject, 
will at the same time be so intimately connected, and 
indeed identified in his consciousness with his purely 
mental operations, that he will, without the least sus- 
picion to the contrary, regard them as entirely the 
result of his mental action on that particular subject, 
and therefore, of necessity, in the constitutional nature 
of things, he wHi feel the subject to be of very great 
and pressing importance to him, and he will inevita- 
bly* ;ud[^« its importance to be equal to the degree of 
the feeling with which he contemplates it. Under this 
morbid influence of his nervous system upon his men- 
tal operations, he will be very likely to think that 
his reputation is seriously asinled, and to cherish the' 
most painful apprehensions that his character will be 
ruined, and all his respectability and prosperity and 
comfort in life destroyed. The more he contemplates 
the subject, the more vividly and energetically will 
his morbid sensibilities call up his conceptions and 
reflections, which will react upon those very sensibil- 
ities, to enhance them exceedingly, and augment the 
nervous irritation, and fear^Uy increase the physio- 
logical depression and derangement of his whole sys- 
tem ; and all this, again, wUl react upon his mental 
faculties, controlling his mental operations, and forc- 
ing upon him the consciousness and the conclusion 
that tul his suffering arises from the ruin of his char- 
acter by the malicious calumny of his heartless and 
wicked persecutors; and he m^y soon come to believe 
that every body is an enemy, and that there is a ^en- 
eral conspiracy to destroy him. At the same time, 
he will be capableof thinking, reasoning, and judging 
with perfect correctness on any other subject, by 
which his morbid sensibilities are not excited ; unless 
his nervous irritation and depression is continually 
kept up by some physical cause (571), and then he will 
either manifest equal insanity on all subjects, or it will 
be exceedingly, difiicult to draw his attention for a 
moment from the conceptions and reflections which 
engross his mind on the one subject; and he will 
constantly recur to that subject as soon as the direct 
efforts cease, which are made to fix his attention on 
real perceptions. 

577* The same important law of the mind is illus- 
trated by a case of inebriation. A person who is 
under the intoxicating effects of tea, coffee, tobacco, 
opium, wine, distilled spirit, or any other narcotic or 
alcoholic substance, is like an organ filled with wind, 
which is ready and pressing to rush out and form a 
tone at any pipe wfiich is unstopped. He is filled 
with a nervous pathos which is ready to manifest 
itself in the form of a moral passion, at any pipe of 
the mind which may be opened to give it vent. Or 
in other words, he is under a nervous excitement, 
which becomes identified with the exercises of the 
mind, or any subject to which his attention may be 

called; and causes him to think, conceive, perceive, 
feel, and act, on that subject, with an ardor and ear- 
nestness commensurate with its intensity. If he be 
engaged in religious meditations or exercises, all his 
nervous excitement produced by the intoxicating 
substance will become to his consciousness purely 
religious feeling arising from the action of his mind 
on the subject which engages his attention (576) ; or 
perhaps he will even attribute it to Divine influence, 
and he will rejoice in the blessedness of his frame of 
mind and tenderness of heart,«nd he will sing, exhort, 
or pray, with a self-satisfaction equal to the tone of 
his feelings, and perhaps with a pathos of eloquence 
which will stir up the sympathies of all around him. 
While in this state, he necessarily judges according 
to his feelings ; religion then is every thing tohim; he 
marvels that every body should not be religious ; this 
world, with all its joys and promises and hopes, is a 
mere delusion; and he is ready, yea, longs, to shake 
off his earthly tabernacle, and hasten to the mansions 
of the blessed. But when his stimulation has passed 
away, it is possible you may find him of a very diffe- 
rent tone and complexion of piety. If he be engaged 
in convivial pleasures, surrounded by cheerful com- 
panions and music and dancing, all his nervous ex- 
citement produced by the intoxicating substance wiQ 
become to his consciousness identified with his mental 
exercises on every subject to which his attention is 
directed (576). If he listens to the music, he will feel 
that it moves him exceedingly, and think he never 
heard it sound better. If he becomes attentive to the 
ladies, he will feel that they never appeared so bright 
and beautiful and fascinating; the civilities and cour- 
tesies of the gentlemen will be regarded as uncom- 
monly generous and agreeable. Or if he thinks him- 
self slighted or insulted, he feels the indignity with 
equal intensity, and the more he contemplates it, the 
more his wrath kindles; and in all the degrees of his 
passion, he judges that his feelings are produced en- 
tirely by the insult, and necessarily measures the im- 
portance and offensiveness of the insult by the inten- 
sity of his feelings; and he vents himself in violent 
language, or seeks revenge by physical force; and 
with fists, clubs, dirks, pistols, or some other weapon, 
rushes in his madness to deeds of violence and outrage, 
and perhaps of blood and murder. 

578. Thus, in all circumstances, the nervous excite- 
ment produced by an intoxicating substance is natu- 
ralljr converted into a moral affection, emotion, or 
passion, on any subject to which the attention of the 
mind is given, and, in the consciousness of the indi- 
vidual, becomes purely the effect of his perceptions, 
conceptions, and reflections on the subject which oc- 
cupies his attention (576) ; and this affection or pas- 
sion, with all the augmentation which it may receive 
from the mental perceptions, conceptions, and reflec- 
tions, necessarily governs the conclusions or judg- 
ment of the mind, in regard to the importance or cha- 
racter of the subject contemplated. And this is 
strictly true of all other general nervous excitements, 
irritations, and depressions, by whatever cause pro- 

579. Hence, therefore, so far as this general law of 
the mind is concerned, strict mental and moral sanity 
requires that the degree of our propensities, affections, 
emotions, or passions, on every subject upon which 
the mind acts, should be exactly equal to the relative 
importance of the subject contemplated, when accu- 
rately compared with all other subjects and things 
which exist, or of which we ever have any notion ; 
or should precisely correspond with what is really 
true in the nature of things. All departure from 
this is a commensurate deviation from strict mental 
and moral sanity. He that desires, loves, hates, ab- 
hors, or in any manner estimates any thing above or 
below its real worth, is in some degree insane. 

580. This is one of the most important general 



laws of the mind ; and the almost universal disregard 
of it in the education of children and youth, is the 
source of immense evil to mankind. It requires that 
in our early education, our affections should receive 
the utmost attention, and that every possible precau- 
tion, pains, and measure, should be taken to prevent 
the association of an improper degree of affection or 
feeling with any of our perceptions, conceptions, or 
reflections (565) ; that when we think of supplying 
any of the real wants of the body, and when we think 
of labor, pleasure, poverty, riches, dress, splendor, 
fame, time, eternity, life, death, virtue, vice, or any 
thing else, our affection should always correspond 
precisely with the real importance of the thing con- 
templated, and thereby enable us to estimate each 
and every thing at its true value,' and thus preserve 
a strict mental and moral and religious sanity. 

581. Now, then, if we bring together the important 
principles which have been explained and illustrated, 
we sh^ll see the philosophy of insanity, and find that 
even in the worst kinds of madness, the mind is still 
strictly true to the same general laws that always 
govern the human mind in all conditions (549). In 
the first place, we have seen (551), that perception 
consists in the impression or sensation received by 
the centre of animal perception (280), from the action 
of the visual, auditory, olfactory, gustatory, and tan. 
gible properties of external things, on our organs of 
sight, hearing, smell, taste, and touch, aud from the 
affections which arise from the internal wants and 
conditions of the body (550), and that conception 
(558) consists in the distinct and vivid reproduction 
of the sensation of perception, without the real action 
of the properties by which it was first produced ; and 
that the sensations of perception (559), being reflected 
to the intellectual faculties, form the thoughts of re> 
flection, which are reproduced in what we call me- 
mory (562). We have seen, in the second place (564), 
that the succession or order in which our perceptions, 
conceptions, and reflections take place, establishes an 
association between them, so that certain perceptioni 
or conceptions will call up certain thoughts of reflec- 
tion, and certain thoughts of reflection may produce 
mental conception : also, our propensities, feelings, 
emotions, and passions, are so associated with our 
perceptions, conceptions, and thoughts of reflection 
(565), that our perceptions, conceptions, and reflec- 
tions, will call up our appetites, emotions, and pas- 
sions^ und these, in return, will call up our reflec- 
tions and conceptions. But though the law of asso- 
ciation is an essential and permanent principle in our 
mental operations, yet the particular associations of 
our thoughts and feelings may and do continually 
undergo changes. Our particular perceptions, con- 
ceptions, reflections, and emotions, are at different 
times, and in different conditions, attended with very 
different associations. We have seen, in the third 
place (566), that a distinct, vivid, and complete per- 
ception and conception, cannot take place at one and 
the same instant ; though the mind may sometimes, 
in a measure, imperfectly attend to both at the same 
instant ; or in other words, we may have imperfect 
visual conceptions, and auditory, olfactory, gustatory, 
or tangible perceptions, at the same time, in a relaxed 
state of the mind. But when we have a distinct and 
perfect visual perception, we cannot have a visual 
conception at the same instant ; and when we have 
a distinct, vivid, and complete visual conception, we 
cannot have a visual perception, in the slightest de- 
gree, at the same instant. Thus, when a person has 
a distinct visual perception of a post or stump, he can 
have no visual conception at the same instant ; but if 
he is excessively afraid of meeting and being killed 
by an Indian, his fears may produce a distinct, vivid, 
and complete conception of an Indian, occupying the 
place of the post, but the instant the conception takes 
place, his perception is lost ; and while the conception 

continues perfect, he can no more see the post nor any 
thing else, than a blind man, and the Indian whicn 
he conceives is as much a reality to his mind as the 
post was which he perceived : and, therefore, it is a 
general law of the mind, which governs it in all states 
and conditions, that our conceptions, when distinct^ 
vivid, and complete, are as much realities to the mind, 
while they last, as our actual perceptions, and that 
the mind cannot possibly know them from realities 
until they have ceased to be (568). We have seen, 
in the fourth place (565), that all general nervous 
irritations, excitements, and depressions, by whatever 
cause produced, call up reflections and conceptions of 
the mind, and are attended with feelings which be- 
come identified, in our consciousness, with our men- 
tal operations, and are greatly augmented by our re- 
flections and conceptions ; the degree of intensity 
always bearing a relation to the irritability of the 
nervous system. And the mind, we have seen (305),. 
cannot, of its own consciousness, discriminate between: 
those feelings which arise from a peculiar condition 
of the nervous system, and which cause our pleasing 
or melancholy thoughts and conceptions, and those 
feelings which are caused entirely by our thoughts, 
conceptions, and perceptions; and, therefore, when 
the mind acts according to its own consciousness, it 
always and necessarily judges that all our emotions 
connected with our thoughts and conceptions and 
perceptions are entirely caused by those thoughts, 
conceptions, and perceptions ; and hence, we necessa- 
rily attribute to the subject on which our mind is ex- 
ercised, the influence or power by which all our intel- 
lectual operations and our feelings in regard to it are 
produced (575) ; and, therefore, we necessarily esti- 
mate the character an^ the importance of that sub- 
ject to us, by the degree of our feelings when con tern- 
plating it. It is, therefore, a general law of the mind, 
which governs it in all states and conditions, that the 
importance, in our estimation, of any subject or thing 
which we perceive or contemplate, is always equal to 
the degree of feeling, emotion, or passion, connected 
with our perceptions, conceptions, and reflections on 
the subject (576) ; and, consequently, our reasonings 
and conclusions, or judgment, always necessarily 
correspond with our feelings. 

582. If, then, an individual is laboring under a 
general nervous irritation, by which distinct and vivid 
conceptions are continually produced, the morbid sen- 
sibilities developed by that irritation, and excessively 
augmented by the reaction of the excited mental ope- 
rations, will greatly increase the vividness and energy 
of his conceptions and reflections, and at the same 
time necessarily cause him to estimate the importance 
of the subjects and things contemplated, according to 
the degree of feeling which attends his mental opera- 
tions. Continual conceptions will therefore not only 
take the place of perceptions, and become realities to 
his mind, but his conceptions and reflections will be 
attended with a degree of feeling which will make 
the things contemplated of the most absorbing inter- 
est and pressing importance to him. New associa- 
tions of thoughts, conceptions, perceptions, and emo- 
tions, will soon be formed, which will aggravate and 
perpetuate the unhappy state of things, and if the 
individual be not speedily restored to health, perma- 
nent intellectual and moral habitudes will necessarily 
be established. 

583. If the nervous irritation and excitement be 
very great, total insanity and raving madness will be 
the result ; but if by slow degrees, the continued or 
frequently repeated action of irritating causes has de- 
veloped a general morbid irritability, rendering the 
nervous system extremely excitable, without keeping 
up a permanent irritation or excitement, then the 
individual will manifest sanity or insanity according 
as his nervous system is composed or excited. In 
this situation, some individuals are. when not excited. 




equally sane on all subjects, and when excited, equally- 
insane on all subjects. Others, from some cause 
or other not difficult to explain, will, while under 
nervous depression, fix the mind on some particular 
subject, and associate their morbid sensibilities with 
it, and necessarily estimate it according to the cha- 
racter and degree of those sensibilities, till it becomes 
of absorbing interest to them (305), and all the rea- 
sonings, conclusions, conceptions, reflections, and as- 
sociations of the mind, obey the controlling energy of 
that interest. These, when the nervous irritation is 
subdued, will be perfectly sane ; but the moment they 
are excited by any means, the morbid sensibilities 
developed by the excitement, being intimately asso- 
ciated with that particular subject, will instantly call 
up the thoughts and conceptions of the mind on that 
subject, and they will manifest insanity on that sub- 
ject alone. But though they manifest insanity only 
on one subject, it is almost impossible, while they are 
under that nervous irritation which causes them to 
manifest the monomania, to fix their attention for an 
instant on any other subject, because their morbid 
sensibilities continually cling to the associated thoughts 
and conceptions, and drag them back, as by an irre- 
sistible instinct, to the all-absorbing subject. And 
in many instances this subject becomes of such thril- 
ling interest to the mind, that the bare naming or 
suggestion of it wiU instantly produce a generaLqer- 
vous irritation, developing the morbid sensibilities 
and all the manifestations of monomania ; and finally, 
the associations become so extensive, that every thing 
external and internal constantly suggests the absorb- 
ing subject. 

584. We see, therefore, that in all species of in- 
sanity, even the worst cases of madness, the mind is 
true to the laws (549) which govern it in all states 
and conditions, and that the body alone is at fault, 
in the morbid irritability, excitements, depressions, 
and sensibilities of the nervous system, by which 
thoughts and conceptions of an improper kind are 
continually called up, and the subjects on which the 
mind acts are made of undue importance, and new 
associations and combinations of ideas are formed, 
and new associations of thoughts and feelings are 

585. Now the question is, whether, according to 
phrenology, the brain is the special seat of this ner- 
vous irritation, and monomania is owing to a morbid 
condition of a single cerebral organ ? or whether the 
^morbid irritability and irritation are common to the 
whole nervous system, and especially the nerves of 
organic life (228), and monomania and other species 
of Insanity are results of that irritation, according to 
the laws which I have explained ? 

580. I confess that I am decidedly in favor of the 
latter opinion, for many more reasons than I can 
assign at this time. I will however adduce a few of 
them. In the first place, there is not a portion of the 
t)rain nor of the little brain which has not frequently 
been destroyed in different individuals, without the 
least manifestation of mental derangement, either par- 
ticular or general. I well know tne reply ; that the 
organs are double, and one eye mav be destroyed with- 
out destroying vision, etc. ; but this argument, even 
if it be tenable, does not meet my position. It may 
answer on the question of the plurality of the cerebral 
organs, but not on that of monomania, as caused by 
the local disease of a particular cerebral organ. In 
the second place, pistol and musket-balls have been 
shot into the brain ; swords, tomahawks, and other 
instruments have been struck into the brain in various 
directions, and in some instances so as to wound corre- 
sponding parts of both hemispheres at the same time ; 
portions of the brain have been discharged at the 
wounds of the skull ; surgeons' fingers and instru- 
ments have been thrust deep into the lobes of the 
brain^ and all this has repeatedly taken place without 

the slightest manifestation of particular or general 
insanity. In the third place, there is no evidence, 
either from post mortem examinations or any other 
pathological facts, that either general or particular 
insanity was ever caused by the disease of a particular 
part of the brain which was strictly local, or which 
did not involve the whole brain ih its irritations. On 
the contrary, all that we know on the subject goes 
decidedly to prove, that when diseases of the brain, 
whether caused by external violence or internal dis- 
turbances, are strictly local; when alf the morbid 
affections are confined to the particular part diseased, 
no manifestations of mental insanity, either general 
or particular, ever take place. And it incomparably 
more frequently happens that post mortem examin- 
ation discloses local disease, change of structure, and 
total destruction of particular parts of the brain, where 
there has been no manifestation of mental insanity 
during life, than where there has; and I contend, 
that when any degree of insanity has attended local 
disease of the brain, that disease has involved the 
whole brain at least, and probably all the nerves of 
organic life, in its irritations ; and I can scarcely doubt 
that in most cases of this kind, the local disease Itself, 
instead of being the cause of the insanity, is only an 
effect of the same cause that produces the insanity. I 
am also confident that the brains of fifty or any other 
number of those who have terminated life after many 
years of chronic mania, either general or particular, 
will, in the average, exhibit as healthy an appearance 
as the brains of an equal number of persons who have 
terminated life after suffering for an equal number of 
years under any other form of chronic disease which 
involves the nervous system of organic life in an equal 
extent of physiological derangement. In the fourth 
place, both general and particular insanity often, if 
not generally, result from irritations which have their 
special seat m the domain of organic life, and perhaps 
most frequently in the digestive organs. I once at- 
tended the dissection of the body of a hospital patient, 
who, according to the opinion of his attending physi- 
cian, a distinguished medical gentleman, died of reli- 
gious mania. His mind had been totally deranged, 
and his madness was at times so violent that it was 
found necessary to confine him ; but the single subject 
which constantly occupied his mind was religion, and 
therefore his case was pronounced religious mania. 
A number of medical gentlemen and students were 
present at the dissection, and it was observed by all 
that the subject was depressed at those parti of the 
head, where phrenologists have located veneration, 
marvellousness, and conscientiousness. On examin- 
ing the subject internally, not the slightest trace of 
disease could be found, till we discovered an intus 
susception of the small intestine, attended with indica- 
tions of a high degree of inflammation before death, 
which extended over a considerable portion of the 
jejunum and duodenum. The subject was very re- 
cent, so that no important post mortem changes could 
have taken place ; and there was nothing to afford us 
the least ground of doubt that both the mental mania 
and the death of the body had been caused by the 
disease seated in the small intestine. 

587. The following is a brief abstract of an inter- 
esting statement given me by an able practising phy- 
sician. " D. CM., a well-digger, 33 years old, full 
habits, was attacked with a relax on Monday, Sept. 16, 
while at labor in a well, but continued labor. Tues- 
day at noon, appetite poor ; took little for his dinner 
beside pickled cucumbers, and went to his labor ; re- 
lax increased, attended with spasms in the muscles of 
the abdomen and lower limbs, and some pain in the 
region of the stomach. At eight o'clock, p. m., I was 
called ; found him vomiting and purging with spasms 
—bled him freely — spasms relieved — ordered warm 
water and a cathartic; he threw up the pickles, 
cathartic operated, after which he took an anodyne 



draught, and rested quietly during night. Wednes- 
day he was relieved ; some soreness remaining oyer 
the stomach, I ordered gruel for diet, and left him. 
Thursday he felt perfectly well, and notwithstanding 
my strict prohibition, and his wife's remonstrances, 
he ate a hearty dinner of flesh, with some pickled 
cucumbers, and went into his garden. In about one 
hour, returned perfectly delirious, and left home for 
the village, where he wandered about till near six 
o'clock, p. m., when he was got home. His delirium 
all this time had been continually increasing. Two 
persons were sent in haste to call me, but not finding 
me at home, one of them called in Dr. W. When I 
arrived, Dr. W. was bleeding him, under the impres- 
sion that he was* laboring under phrenitis. On en- 
Suiry I learned from his wife what he had done, and 
[lathe was quite well at noon before he ate his din- 
ner ; and I told Dr. W. that I suspected the cause of 
the delirium to be in the stomach or bowels. He 
thought it was in the head ; but as he considered the 
patient mine, he left him to me, and withdrew. I 
immediately directed measures to evacuate his stom- 
ach and bowels. His symptoms had been very little 
relieved by the bleeding, although it was copious, say 
thirty ounces, and there was no symptom present to 
indicate any derangement of the chylopoietic viscera. 
On making pressure, however, over the stomach, he 
flinched ; and on drinking a glass of cold water he 
manifested uneasiness at the stomach. There was no 
sufi^usion of his face and eyes with blood ; his eyes 
were brilliant, and their whites of a pearly whiteness ; 
their expression mild and playful. His thirst was 
incessant. He would not sufiier me to examine his 
tongue. An emetico-cathartic was administered, 
which operated several times. Not being satisfied 
with the catharsis, I ordered castor-oil, supposing 
from the account given by the attendants that the 
emesis had been quite suflicient to evacuate the con- 
tents of his stomach at least ; for they said he had 
vomited four or five times severely. At ten in the 
evening his bowels had been moved seven or eight 
times, and he had vomited about the same number of 
times ; but his delirium was not relieved. He had 
thrown up a little of what his attendants supposed to 
be a part of his dinner, and was still a little sick at 
the stomach. Warm water was ordered to be taken 
freely, which brought on full vomiting again. After 
several severe efforts, he threw up a mass of what 
proved on inspection to be flesh and pickled cucum- 
bers. From that moment his delirium ceased, and 
he immediately recovered." This medical gentleman 
is a full believer in phrenology. 

588. I might add numerous cases of this kind, 
many of which have fallen under my own observa- 
tion ; but I deem it unnecessary. Puerperal insanity 
most unquestionably results from irritations located 
in the domain of organic life, and involvinc: the whole 
nervous system. In short, I fully believe that at least 
ninety-nine cases in a hundred of chronic mania ori- 
ginate in the irritations of the nerves of organic life, 
and that when cerebral disease or change of structure 
supervenes, it is the result of the same cause that pro- 
duces the mania, and is preceded by manifestations of 
mental insanity. I do not think, therefore, that mo- 
nomania in any degree proves a plurality of organs in 
the brain.* Yet I freely admit that, all my reason- 
ing being true, there may still be a plurality of cere- 
bral organs, and I do not affirm that there is not ; 
but I contend that it is a matter which yet requires 

Sroof ; and whether true or not, the phrenologists 
ave evidently made the contents of the skull too 

* If the views I have presented be correct, then monomania, 
as well as other kinds of insanity, should be regarded and treated 
as a symptom of general morbid irritability, sensibility, and sym- 
pathy, rather than as a local disease of a particular portion of the 

exclusively the machinery and source of the mental 
and moral powers and animal propensities. 

589. The brain, whether consisting of a single 
organ or, of a system of organs, is unquestionably Uie 
seat of intellect (260), but it is not equally evident 
that it is the seat of all the animal propensities; 
though it is possible that each propensity has its spe- 
cial organ of perception in the brain. We know that 
if the nervous communication between the stomach 
and the centre of animal perception be cut off,^ the 
animal can have no perception of hunger ; and it is 
very certain that hunger is a special sense (550), pro- 
duced by a peculiar physiological condition of the 
nervous tissue of the stomach, and perceived by the 
animal centre ; but neither the hemispheres of the 
brain nor the lobes of the little brain are essential to 
the animal perception of hunger, or desire for food 

590. We are told that some men can feel the exer- 
cises of particular parts of their brain in their mental 
operations ; but I leave those to believe such things 
who can, and I ask if ever any one felt his brain to 
be the seat of his propensities and emotions ? Have 
not mankind in all ages, from mere feeling or consci- 
ousness, always referred these emotions to the epigas- 
tric region ? What lover, or parent, or patriot, in 
the g^sh of his emotions, ever instinctively laid his 
hand on the back of his head, and spoke of the ardor 
of his feelings ? (534, Nos. 4, 5, 7). But shall I be 
asked if I intend to affirm' or imply that the mind has 
one seat, and the propensities and sentiments another, 
and that the abdominal viscera (313) have an inde- 
pendent power of sensibility within themsdves, and 
constitute the special organism of the animal propen- 
sities and moral sentiments ? I reply, that I mean 
simply to affirm that there is a oneness in the nervous 
system of the human body ; that to a certain extent, 
and for certain purposes, the nerves of organic and 
of animal life constitute a single whole ; and that the 
point of unity or centre of perception of this single 
whole is at or near the top of the medulla oblongata 
(280). In the domain of organic life, we have seen 
(219), that there are special centres for special pur- 
poses, and a common centre (218), which presides over 
the whole internal economy ; and so far as the wants 
of the vital economy require the exercise of voluntary 
functions, the animal centre has a perception of those 
wants (294). Or, in other words, the vital economy 
manifests those wants by producing certain physiolo- 
gical conditions of the tissues of certain organs in its 
organic domain ; and the animal centre, by means of 
nervous connexions established for the purpose, per- 
ceives those physiological conditions, and thus they 
become special senses; and as strictly so as mht, 
hearing^ smell, taste, and touch (550). The animal 
centre, then, as a unit, does, as it were, throw out its 
feelers into every portion of the body internally and 
iextemaUy. By the internal feelers it perceives those 
physiological conditions of the organic domain which, 
being perceived, constitute the sense of hunger, thirst, 
etc. ; and thus it has cognizance of all those internal 
conditions which directly relate to the voluntary 
powers. By its external feelers it perceives those 
impressions made by the qualities of external things, 
which constitute the senses of touch, taste, sm^, 
hearing, and vision ; and thus we are enabled to p»- 
ceive both our internal wants and the external sup- 
plies. The perceptions of the animal centre ar^ all 
instantly reflected to the intellectual organ or organs, 
and produce thoughts of reflection in the manner I 
have described (559). Moreover, as we have seen, 
the brain and all the nerves of animal life continually 
and entirely depend on the functional integrity of the 
nerves of organic life for their own functional powers 
(209, 260) ; and, therefore, though we have no special 
sense of perception by which we are informed of all 
the functional aberrations in the domain of organic 



life, ^et the brain always sympathizing in the general 
conditions of that domain, we are conscious of the 
effect without knowing the source (305). 

591. On the whole, then, though I do not wish to 
be considered as an opposer of the theory of Dr. Gall, 
but am strongly disposed to favor its general princi- 
ples (543), yet I must contend that while the brain, 
either as a single organ, or as a system of organs, is 
the special seat of thought, the whole nervous system 
is so intimately connected with the brain as its intel- 
lectual and moral instruments (590), and the intellec- 
tual and moral operations of the brain are so closely 
associated (565) with the conditions and influences of 
the nerves of organic life (305), that the intellectual 
and moral philosophy of man cannot be accurately 
understood without a just knowledge of the nervous 
system as a whole ; and that the physiological laws 
with their important relations constitutionally estab- 
lished in the organic domain, are of incomparably 
more importance to the philosopher, the philanthro- 
pist, and the Christian, than the external shape of the 
skull, or even the internal structure of the brain. 
For, admitting all that phrenology claims in regard 
to cerebral organization, it is still true that the intel- 
lectual and moral character of man can only be con- 
stitutionally reached through the medium of the 
nerves of organic life (306) ; or, in other words, it is 
only by a proper attention to the physiological laws 
of the domain of organic life, that we can justly hope 
to have such an effect on the shape and condition of 
the brain, and other parts of the body, as will secure 
healthy wisdom, virtue, and happiness, to the human 

592. My apprehension is, that the intellectual and 
moral science of man is far more profound and intri- 
cate than phrenology contemplates, and cannot be 
fuUy understood without a knowledge of all the pro- 
perties and powers of the whole human eystem ; and 
therefore, instead of limiting our observations and 
investigations to the head, in order to find out what 
a man is, we should extend them over the whole 
organiiation, and endeavor to ascertain the particular 
and the general laws of animal, intellectual, and 
meoriU physiology, that we may not only know what 
man. is, butal^ what he ought to be, and how. to 
mak^ and keep him so. 


CittBffral Urn of relation between the initincts and the voluntary 
powfra-^Bntte reason — General law of relation between the 
butiiicta and cerebral faculties— Man and animals under the 
same law— But man can deprave himself and multiply his 
w«Bt»— Not ao other animals — Artificial wants of man act on 
his cevd»Bl organs the same as the natural wants — Man's supe- 
rior iatellect sinks him deeper in depravity— What he would 
Im without moral powers— The end for which his moral powers 
are established— These, his distinguishing and most exalting 
atfribatfti — Relations of man to his Creator and to his fellow 
creatures— The Goqiel agrees with phy&iology— The moral pro- 
bation ot man- His moral ability and inability — Conscience, 
what! — ^Moral sense innate ; its power — A false or true consci- 
•BJBO^ how f<Mrmed — Moral sense, more or less active and powex- 
ivlr^ESkot of morbid sensibility of the nervous sys:em on the 
BMural, sense and conscience — False conscience; its sources — 
Man naturally and necessarily religious— Superstition, bigotry, 
ftaaticlsm- Man's moral responsibility — Other moral faculties 
vusdwr the same law*. 

693. We have seen that the nerves of organic life 
pi:eside over all the functions concerned in the nourish- 
ment, growth, and general sustenance of the body 
(223, 227, 228) ; and that so far as digestion, absorp- 
tion, respiration, circulation, secretion, excretion, 
organization, the regulation of temperature, etc., are 
•considered, the animal, like the vegetable, is, in a 
state of health, destitute of consciousness (208) ; and 
could the animal, like the vegetable, be regularly sup. 
plied with nourishment without the exercise of volun- 
tary powers, the animal body, like the plant, might 

be developed, attain to its full size, live out its consti- 
tutional period, and die and decav without the least 
consciousness of its existence (294). 

594. But the animal body is constituted with such 
relations to the external world, as require the exercise 
of voluntary powers to supply the wants of its inter, 
nal economy (209). Hence it is furnished with an 
apparatus of nerves and organs adapted to its external 
relations (283). This apparatus (233) consists of the 
nerves of animal life, which are endowed with pecu- 
liar properties and powers (294), by which the animal 
is made conscious of its existence, and enabled to per. 
ceive its internal wants, and those external properties 
and things by which its wants aie supplied (209); 
and of the muscles and bones employed in voluntary 
motion, by which it is enabled to approach and seize 
those things which it perceives and wants (233). 

595. The internal wants, I have said (590), are 
attended with certain physiological conditions of the 
organs, and these conditions being perceived by the 
centre of animal perception (280), become the special 
senses of hunger, thirst, etc. (589\ In the lowest 
orders of animals (209), the animal consciousness is 
extremely feeble, and the animal perceptions and 
voluntary functions are purely instinctive and rudi. 
mental. The animal is scarcely elevated above the 
vegetable (209). As we ascend the scale of animal 
existence, we find animal consciousness and perception 
more and more vivid and powerful, and the voluntary 
faculties more and more developed and active. But 
from the lowest to the highest orders of animals, in- 
cluding man, it is a universal law of the animal 
kingdom, that the domain of organic life manifests 
its wants to the centre of animal perception in such 
a manner as to produce a strong propensity in the 
animal to exercise its voluntary powers for the supply 
of those wants. These propensities are called in- 

596. In many of the lower orders of animals, the 
voluntary powers are purely the instruments of the 
animal instincts. Without an act of reasoning or of 
reflection, the animal is moved by the sense of its 
wants, to exercise its voluntary powers in such a 
manner as to satisfy the propensity ; and in obeying 
its internal instinct, it instinctively employs its in- 
stinctive powers of external relation connected with 
its voluntary powers ; and by smell, taste, and other 
perceptive senses, feels out the substances adapted to 
its wants, and thus fulfils the final causes of its organ- 
ization. The voluntary powers of the higher orders 
of animals are equally obedient to the instinctive 
wants or propensities, but their exercise is attended 
with something more of thought and reasoning. The 
rudiments of brute reason are probably to be found uk 
all the vertebrated animals ; but they are more and. 
more developed as we ascend the scale towards man. 
And there is little ground of doubt that the reaaoning 
powers of animals bear a precise relation, as to their 
extent, to the developments of the brain. The mon- 
key tribes, the elephant, the dog, the fox, the horae, 
the swine, and several other animals, give the most 
unquestionable evidences of their powers of reason 
and reflection. Nevertheless, whatever be the extent 
of the powers of brute reason in animals, those powers 
are always perfectly subservient to the instinctive 
wants of the body. All the reasoning and reflection 
ever manifested by the horse, dog, elephant, etc., are 
excited by their instinctive propensities, and are only 
exercised in conformity to those propensities, or for 
the purpose of gratifying them, and never for the 
purpose of resisting or restraining them. It is 
therefore a general law of the animal kingdom, that 
the cerebral faculties, whatever they may be, are sub- 
servient to the wants of the body ; and all the intel- 
lectual and voluntary powers naturally concur with 
the animal propensities and seek their gratification. 

597. It is, as I have stated (520), entirely certain, 



that whatever be the labstratum of the sensorial 
power of the human brain, it resides in and acts 
through the organized matter of the nervous sub- 
stance, during our present state of existence, precisely 
the same as if it were merely a property of that vital, 
ized matter, and all its powers and manifestations are 
subject to precisely the same laws as govern the 
powers and manifestations of vitality. Hence, so far 
as the instinctive wants and animal propensities, and 
their relation to and influence upon the intellectual 
and voluntary powers, are considered, man is in the 
same general predicament with the lower animals : 
all his internal wants and propensities appeal to his 
intellectual and voluntary faculties, and excite their 
action, and naturally cause them to concur with, and 
seek the satisfaction of, the bodily desires. And 
although there is an almost infinite distance between 
the reason of man and that of the highest order of 
the lower animals, yet the philosophv of his reascming 
is precisely the same as that of tlie elephant, the 
horse, etc., and consequently it is governed by the 
same general laws. But man's superior intellectual 
and voluntary powers not only increase his ability to 
supply his bodily wants in all the varying circum- 
stances of seasons and conditions, but also increase 
his power of multiplying those wants, by his artificial 
modes of supplying them, and by the artificial cir. 
cumstances of social and civic life. 

598. The horse and ox and other animals, like man, 
have the special sense of thirst, or natural want of 
water, but they have neither the reasoning nor the 
voluntary powers to supply this want with any thing 
else but water ; and, therefore, from birth to death, 
and from generation to generation, they only feel the 
same natural and simple want, and are always satis, 
fied when that want is supplied with good water; but 
out of this simple and single want of his body, man 
venerates a thousand artificial wants, which become 
ingrafted upon his body, and exert their influence 
upon his intellectual and voluntary powers in pre- 
cisely the same manner as his original instinctive 
wants do, and always with a more despotic and im. 
perious energy, and with a continual and powerful 
tendency to excess. The same is true of the special 
sense of hunger : in the lower animals, it is aiwavs 
equally simple and natural, unless depraved by tne 
artificial training of man ; but man multiplies this 
simple natural want into a thousand artificial ones, 
which exert a controlling and arbitrary influence 
upon his intellectual and voluntary powers ; and in 
the same manner, every other natural want and sense 
of the human body are multiplied by man to the ex. 
tent of his capabilities (21) ; and out of these innu. 
merable wants which are ingrafted upon the natural 
propensities and sensibilities of his body, spring a 
multitude of others in connexion with the social and 
civil institutions and customs of society. These 
thousands of artificial wants soon come to be so inti- 
mately and completely associated with the natural 
wants of the body, that few know the difference be- 
tween the natural and the artificial ; and all of them, 
with different degrees of energy and despotism, press 
their demands upon the intellectual and voluntary 
powers, urging or compelling those decisions of the 
mind, and those exercises of the voluntary powers, 
by which they can be satisfied or indulged ; and upon 
precisely the same principles of intellectual and moral 
philosophy as govern the action of the original in- 
stinctive wants of the body, upon the cerebral facul- 
tier (666, 676). 

599. But in thus multiplying his wants, man neces- 
sarily not only depraves the natural instincts, pro- 
pensities, and sensibilities of his body, and increases 
the force and despotism of his wants upon his intel- 
lectual and voluntary powers, but he also impairs his 
mental faculties, and deteriorates his whole nature, 
and tends to the destruction of mind and body. 

600. Hence, therefore, were man only elevated 
above the other animals by superior intellectual and 
voluntary powers, his natural elevation would answer 
no other end than to increase the distance of his fall, 
and the depth of his degradation and misery. He 
would, indeed, be the vilest and most wretched of all 
terrestrial things. With all his intellectual and 
voluntary powers subservient simply to the supply of 
his bodily wants, and those wants multiplied beyond 
number, and increased continually in despotism and 
depravity, his superior powers would only be a supe- 
rior abikty to make himself miserable, and to destroy 
himself and others. His reasoning powers would be 
employed with little more than the excitements of his 
appetites and feelings, and in securing the means of 
his self-indulgence, and in devising the crafty or the 
violent measures by which he could procure or des- 
troy whatever his lusts or passions demanded; his 
judgment would be but the dictates of his propensi- 
ties; desire would constitute his only principle of 
action ; and this would lead him downward, deeper 
and deeper into the abyss of animal depravity, and 
subjugate his intellectual powers to more and more 
degrading and debasing slavery to his sensuality. 
Never would his reason remonstrate with his pas- 
sions ; never would his judgpnent condemn his indul- 
gence ; strength would constitute the right of prece- 
dence, and power the law of possession ; and man 
would prey upon his fellow creatures with an energy 
and cruelty, by so much the fiercer and more des- 
tructive and terrible than the most ferocious of other 
animals, as he possessed superior intellectual and 
voluntary powers to deprave himself, and to devise 
and carry into execution more crafty and skilful plans 
of destruction. 

601. To prevent this natural tendency of man*s 
animal nature, and to excite his intellectual powers 
to elevated and extensive efforts in the attainments 
of knowledge and wisdom, a wise and benevolent 
Creator has endowed him with moral foweiis, and 
made him the subject of moral government. 

602. Thus God has created matter, and impressed 
upon it those primary laws (89), by which it enters 
into the various forms of the inorganic world, and by 
which those forms are governed as individual masses f 
and upon the common matter of the inorganic world 
he has superinduced still higher laws of action and 
constitution (110), by which it is made to enter into 
the arrangements and forms of living organized bo- 
dies ; and upon organized matter he has superinduced 
still higher laws of constitution, by which living- 
bodies are endowed with a consciousness of their ex- 
istence, and with the power of perceiving their inter- 
nal wants, and of perceiving and procuring the exter- 
nal supplies (114, 138) ; and upon animal conscious- 
ness and sensibility he has superinduced still higher 
laws of constitution, by which the animal is endowed 
with intellectual powers (166) ; and finally, upon the 
associated animal nature and intellectual powers of 
man, God has superinduced moral powers. It is, 
therefore, the moral nature of man which gives him 
his highest elevation in the scale of being, and places- 
him at the greatest distance from his fellow animals,, 
and nearest to angels or to devils. 

603. By this wonderful union of intellectual and 
moral powers with organized matter, man alone, of 
all terrestrial beings, is brought into a twofold rela- 
tion to his Creator. In his material nature, man, in 
common with all other material forms and substances, 
holds a fixed relation to his Creator as the great, first, 
and continually efficient Cause by which matter and 
all material forms and properties and powers are what 
they are. This relation only embraces the natural 
attributes of God. In his moral nature man holds a 
fixed relation to his Creator, as an infinitely true and 
just and benevolent and good and holy Bein^ and 
Judge and Father. But as there is of necessity an 



eisAtial and perfect harmony between the natural 
and the moral attributes of God, so is there a perfect 
harmony between the natural and moral relations 
which man holds to his Creator ; so that the perfect 
fulfilment of the one requires the perfect fulfilment 
of the other. That is, the constitutional laws which 
govern the living, organized body of man, and on 
which all its physiological properties and powers and 
interests depend, harmonize most perfectly with the 
constitutional laws which govern his intellectual and 
moral nature. So that the highest and best condition 
of the human body requires a perfect obedience, not 
only of its own physiological laws as living organized 
matter, but also of the constitutional laws of the in- 
tellectual and moral nature associated with it ; and the 
highest and best condition of man's intellectual and 
moral nature requires the perfect obedience, not 
only of its own constitutional laws, but also of the 
constitutional laws of the body as living organized 
matter : and consequently, the violation of the con- 
stitutional laws of the one is necessarily attended 
with an infraction of the constitutional laws of the 
other. Hence, therefore, no moral or civil law or 
religious doctrine can be adapted to the highest and 
best condition of man's moral nature, which is not 
strictly consistent with the physiological laws of his 
body ; and on the other hand, no bodily habit, in. 
dulgence, or regimen, can be adapted to the highest 
and best condition of his body, which is not strictly 
consistent with the constitutional laws of his intellec- 
tual and moral nature. And it is a deeply interest- 
ing and incontrovertible fact, worthy of all considera- 
tion, that if one who had the most perfect knowledge 
of the physiological laws of the human body, should 
draw up a code of moral and religious laws for man, 
which should in every principle and point be strictly 
conformable to the constitutional laws of man's bodily 
and moral nature, and most philosophically adapted 
to the condition and relations of man, he could not 
possibly produce a code more wisely fitted to the con- 
stitutional truth, and to the highest and best condi- 
tion of human nature even in this world, than is con- 
tained in the New Testament of our Lord and Saviour 
Jesus Christ. 

604. The animal nature of man may be considered 
as the basis of his human existence. Its passions, 
its propensities, its desires, with all the artificial 
wants that are ingrafted upon the bodily instincts 
and sensibilities, constitute the primary and principal 
elements of activity to his mental powers, and tend 
continually to cause his rationality to concur with 
his animal indulgence, or to consent to and provide 
for the gratifications of all his sensual and selfish 
appetites and desires, both natural and artificial (598). 
And this is what the apostle Paul, who was one of 
the most profound philosophers that ever lived, calls 
tJie minding of the flesh ; and with equal physiological 
and moral and religious truth, he declares that the 
minding of the flesh is death ; for, as we have seen 
(599), it inevitably leads, if unrestrained, to the 
speedy destruction of the body, and of the mental and 
moral powers, and to the extermination of the race. 
But the moral powers which God has constitutionally 
established in human nature (fK)l), come in to regu- 
late the carnal nature of man, with reference to 
moral law, which, as we have seen (603), perfectly 
harmonizes with the physiological laws of man's 
nature. And the whole bearing of moral law on 
human nature, is to hold the carnal passions, propen- 
sities, and desires (598), in perfect subjection to a 
rationality which is enlightened and governed by 
moral truth. 

605. Moral truth says, Thou shait love that stu 
premely which it intrinncally most excellent and worthy 
of being loved, which is the moral character of God, 
and which, being supremely loved, will not only 
secure thy own highest and best condition, but the 

supreme love of which, in thee, is most perfectly com- 
patible with, and conducive to, the highest and best 
condition of thy fellow -creatures : but carnal nature 
says, / wiU love thai supremely to which I have the 
strongest intrinsic propensity, which is self-indulgence. 
Here, then, is the conflict of man's moral probation : 
between his carnal nature, with all its natural and 
acquired wants and appetites (598), and God's moral 
truth ; for the flesh lusteth against the spirit of truth, 
and the spirit of truth striveth against the flesh ; and, 
therefore, the minding of the flesh, beyond the true 
and proper fulfilment of the constitutional laws of 
human nature, or beyond the true and proper supply 
of the real wants of the body, is, of necessity, in the 
nature of things, contrary to supreme love to God, 
for it is not obedience to the laws of God, neither in- 
deed can be, because it is a direct transgression of 
those laws (603). 

606. The moral nature of man is established by the 
Creator to preside over and control this conflict, and 
is made responsible at the bar of God's eternal and 
immutable truth for the issue, and necessarily liable 
to the penalties which result from the infraction of 
God's laws. On the one hand, man's carnal nature 
is continually pressing for indulgence, and exerting 
its seductive influences on the rational powers, to draw 
them into concurrence with its propensities and appe- 
tites ; while on the other hand, the moral truth of 
God, which perfectly harmonizes with the natural 
truth of God (603), constitutionally established in the 
physiological laws of the human body, demands of 
man's moral nature the entire subjugation of his car- 
nal passions, propensities, and appetites, to the re- 
quirements of moral truth, and declares that he who 
desireth to transgress, is essentially guilty of the act. 

607. The whole controversy of the schools con- 
cerning man's moral ability and inability may, there- 
fore, be resolved simply to this, namely, his ability to 
will and act in obedience to moral truth, subject as 
his intellectual and moral powers are to the influences 
of his carnal nature (598). His moral ability is 
always precisely equal to the degree in which his 
moral powers hold his carnal nature in subjection to 
moral truth; and his inability is always precisely 
equal to the degree of influence which his carnal 
nature exerts upon his intellectual and moral powers, 
in opposition to moral truth. The more the intellec- 
tual and moral powers of man are under the control 
of his carnal nature, the greater is his moral inability 
to perceive, understand, and comply with the require- 
ments of moral truth ; and therefore whatever tends 
to deprave and multiply the carnal passions, propen- 
sities, and appetites of man, or in any degree to ex- 
cite them and increase their power, does necessarily 
and directly increase his moral inability to perceive, 
understand, and comply with the requirements of 
moral truth, and to obey the constitutional laws of 
his nature. 

608. Let us now recapitulate for a moment, for the 
purpose of bringing our argument to a focus. Man, 
then, has an animal nature, with constitutional laws 
common to the elephant, the horse, the ox, and other 
animals (595). He is endowed with voluntary and 
intellectual powers immeasurably superior to other 
animals, but established with the same relations to 
the bodilv wants and appetites (595), and with the 
same philosophy of action as those of the monkey, the 
elephant, the do^, etc. (597). The lower animals 
have neither the intellectual nor the voluntary powers 
to violate the constitutional laws of their natures, to 
any serious extent, and thus deprave themselves, de- 
teriorate their natures, and exterminate their species 
(598), and therefore they do not require a knowledge 
of the constitutional laws of their nature, and of the 
laws of relation which grow out of them. But man 
has both the voluntary and intellectual powers and 
the natural propensity to violate the constitutional 



litws of his nature, and thus deprave, deteriorate, and 
destroy himself. The good of man as an individual 
and as a species, therefore, requires that he should 
both know and obey the constitutional laws of his 
nature ; and accordingly God has endowed man with 
moral powers (601), which are constituted with fixed 
and precise relations to his animal nature on the one 
hand, and to the moral character of God on the other ; 
and the office of these moral powers is to prompt man 
to know and to obey the concordant, constitutional 
laws of his animal and moral nature (604), and thus 
secure his own highest good and happiness, and pro- 
mote the highest good and happiness of his fellow- 
creatures, and thereby fulfil the divine scheme of 
benevolence which has, in the con«titutional nature 
of things, identified the supreme glory of God with 
the highest good and happiness of man. 

601). To quicken man's moral powers to the faithful 
and unremitting performance of this important duty, 
God has from time to time addressed to him such 
moral instructions, and placed before him such mo- 
tives, as his moral and intellectual condition fitted 
him to receive. In the morning twilight of the intel- 
lectual and moral world, when man's moral percep- 
tions were feeble and indistinct, and his knowledge 
was limited to sensible things, the motives which God 
placed before him to induce him to know and obey 
the constitutional laws of his nature, were bodily 
health, and long life, and worldly prosperity, and 
honor. But when God, by the continued operations 
of his great scheme of benevolence, had prepared the 
way for the introduction of a higher dispensation of 
motives, he brought life and immortality to light, and 
placed before man not only bodily health and long 
life and happiness in this world, but also moral purity 
and god-like excellence here, and eternal life and 
glory beyond the grave, as motives to induce him to 
know and obey the constitutional laws of his nature. 

Now, then, let us endeavor to understand the true 
nature and philosophy of man's moral powers. 

610. All mankind are conscious of possessing an 
attribute or power which, in our language, is called 
the CONSCIENCE. But theologians, metaphysicians, 
and philosophers, have seemed to be quite as much in 
the dark as the unlearned multitude, concerning the 
real nature and power of the conscience. Some tell 
us that it is that faculty of the soul which discrimin- 
ates between right and wrong, or which approves of 
what is right and disapproves of what is wrong, 80 
far at least as to establish the great lines of demarca- 
tion between right and wrong, between vice and 
virtue. Others, carrying this view still farther, 
assert that the conscience in in every breast, an 
innate rule of right which each individual is bound 
to obey, and by which each may measure his own 
actions ; and, therefore, that in all matters of consci- 
ence, man has a natural and inalienable right to entire 
and unrestricted liberty. Others, again, perceiving 
that the consciences of different persons under differ- 
ent circumstances and with different educations, 
sanction and enforce things entirely different and 
diametrically opposite, are led to believe and assert 
that conscience is wholly a result of education, and, 
therefore, no criterion of right or virtue. 

611. But these opinions are all founded on errone- 
ous notions of the nature and powers of man's moral 
faculties. Every human being who is not an idiot, 
and who is old enough to understand the exercises of 
his own mental and moral powers, has something 
within him which, when excited, acts determinate! y, 
and definitely approves or disapproves of specific 
moral actions and qualities. This is what all men 
call Conscience. But this is neither a simple nor an 
innate power or faculty of the soul ; it is of a complex 
character, and, as such, wholly the result of educa- 
tion ; and is with no degree of certainty, a rule of 

612. It is not, however, more certain that the ^- 
tellecual faculties of man are innate, than it is that 
the MORAL SENSE is an innate power, a constitutional 
principle in the moral nature of man. But this is 
not to be confounded with the conscience^ in correct 
philosophical reasoning. It is in no degree the result 
of education ; nor can it be in any manner educated, 
except in being rendered more or less susceptible and 
active and powerful ; but still, it always necessarily 
remains the same simple moral sense : the same in 
the Pagan, the Jew^ the Mahomedan, and the Chris- 
tian ! — the same in a Hottentot, a Newton, a Paul! 
— ^the same simple moral sense which informs no man 
what it right or what is wrong ; and has no more 
power than the sense of hunger has, to discriminate, 
even on the broadest grounds, between right and 
wrong, between vice and virtue. It is ever, and 
under ^11 possible circumstances, the same simple 
moral sense, out of which grows the consciousness 
that there is a distinction between right and wrong, 
and a consciousness of moral responsibility ; and, 
when excited to perform its function, its definite, 
determinate, and only language is : — * be right !^ 
BE RIGHT !' But what that right is, it has no power 
to ascertain. For this it depends entirely on the in- 
tellectual faculties, which collectively, in their mental 
unity, I call the understanding. Whatever tie 
understanding, acting under the influence of the 
moral sense, fully determines to be true or right, the 
moral sense receives as right ; and afterwards, when 
excited in relation to the same thing, this complex 
power resulting from the co-operation of the moral 
sense and understanding, prompts the soul to obey it 
as right. Thus, suppose the proposition be laid before 
the mind of a man totally uneducated in morality and 
religion, and who knows nothing of the customs and 
opinions of mankind, that it is his moral duty to kill 
his parents when they become so old and infirm as 
not to be able to support themselves. His moral 
sense can neither intuitively nor by any process of 
reasoning tell him whether the proposition is true or 
false. His understanding only can examine and 
weigh the evidence in the case, and come to the con* 
elusion or decision as to the truth or falsity of the 
proposition. But while the understanding is doing 
this, the moral sense can more or less energetically 
and continually exert an influence upon it, which 
says, ' be right ! be right !' and thus cause the under- 
standing to examine and weigh the evidence in the 
case, with greater attention, diligence, and scrupu- 
losity. And if by any means die understandiuff, 
acting under this influence of the moral sense, u 
brought to the full conclusion that the proposition is 
true, the moral sense has no power in itself to test the 
accuracy of the conclusion ; and, therefore, necessarily 
receives it as true : and this conclusion, or mixed re- 
sult of the simultaneous action of the moral sense on 
the understanding, and of the understanding on the 
proposition, becomes a definite and determinate moral 
sentiment of the soul, which is so intimately asso- 
ciated with the moral sense, as to be instantly called 
up as a dictate or determinate impulse of the moral 
sense, whenever this simple power is excited to action 
in reference to the same proposition. And this definite 
and determinate moral sentiment is what all men caJl 
the conscience. 

613. We see, then, that in this supposed case, the 
moral sense of the individual cannot possibly tell him 
whether it is right or wrong for him to kill his pa- 
rents when they become old and helpless. It can only 
tell him to be right. But the conscience formed in 
the manner I have described (612), tells him definitely 
and determinately that it is right and duty for him to 
kill his parents when they become old and helpless. 

614. Now change the circumstances of this indivi- 
dual, and let the same proposition again be presented 
to his mind, and let his moral feelings be excited on 



the subject, and all the real evidence in the case pre- 
sented to him in a true light; his conscience will 
come up at once, and say definitely and determinately, 
' it is right to kill the parents/ etc. But if the new 
circumstances and new array of evidence can shake 
his confidence in the former conclusion of his under, 
standing, and cause him to doubt the correctness of 
it, the voice of his conscience will become feebler and 
feebler as the strength of his doubts increases, while 
the voice of his moral sense, with more and more 
energy and importunity, will say, * be right ! — be 
right !* and if, under this influence of his moral sense, 
and in view of all the evidence which is now present- 
ed to him, his understanding comes fully and confi- 
dently to the conclusion that the proposition is false, 
and that it is wrong to kill his aged and infirm pa- 
rents, and right and duty to protect and cherish them, 
then this conclusion will become a definite and deter- 
minate moral sentiment of his soul, taking the place 
of the former one. And now his conscience will de- 
terminately tell him that it is wrong to kill his aged 
parents. So that the conscience of the same indivi- 
dual may at one time tell him it is right, and at an- 
other time that it is wrong, to kill his aged and help- 
less parents. Yet in all this, the moral sense under- 
goes no change. Its simple, single, only, and unerring 
cry, is always, when excited to action, ' be right ! be 
right !' 

615. But tbe moral sense, I have said, may be cul- 
tivated as to the degree of its energy or influence. 
And in this respect its laws are the same as the com- 
mon physiological laws of the body. It may always 
be extremely feeble from want of proper exercise, so 
that it will never with energy urge the understand, 
ing to ascertain the truth on any point. It may also 
be greatly impaired and almost totally obliterated by 
the continued violations of the constitutional laws of 
human nature (603). Whatever, in food or drink, 
or any other bodily indulgence or habit, impairs the 
sensorial power of the nervous system (697), com- 
mensurately impairs the moral sense ; and all inten- 
tional violation of the constitutional laws of man*s 
moral nature, every voluntary departure from strict 
righteousness, truth, holiness, etc., necessarily impairs 
the moral sense ; and when these causes are combined, 
and their action continued, they often so completely 
blunt or deaden the moral sense, that the apostle 
Paul justly compares the effect to the searing of a hot 
iron. On the other hand, the moral sense may, by 
much exercise and careful cultivation, be rendered 
exceedingly vigorous and active and delicate, so that 
it will on all occasions, and in every, even the most 
inconsiderable, moral action and operation of the 
mind, energetically and healthfully urge the under, 
standing to decide aright, to act aright. But the 
moral sense may also become excessively and mor- 
bidly active and acute, causing the most intens§moral 
suflTering, and even producing monomania or general 
insanity. Whatever in food or drink, or any other 
bodily habit or indulgence, produces a general mor- 
bid irritability and sensibility in the nervous system 
(571)9 always tends to produce a morbid excess m the 
moral sense of conscientious people, filling the mind 
with unhealthy scruples and remorseful anguish, and 
perhaps despair, and sometimes rouses it up in most 
fearful energy, in those who have never before at- 
tended to its wholesome monitions, and fills them with 
the most terrible remorse and horror ! Religious 
exhortations and appeals, also, which are of an im- 
passioned and terrific character, and which greatly 
excite the moral sense, without properly enlightening 
the understanding, always tend to produce a morbid 
excess in the moral sense, and frequently cause par- 
tial or total insanity, and very rarely lead to real 
and permanent good. 

616. When the moral sense is feeble and inactive, 
it does not throw a proper degree of influence on the 

operations of the understanding, but leaves it either 
to neglect, or carelessly %o examine, or unfairly weigh 
evidences, and thus come to erroneous conclusions, 
and form a false conscience. When, on the other 
hand, the moral sense hy any means is rendered mor- 
bidly active and energetic, it throws so vehement and 
distracting an influence on the understanding as to 
impair the accuracy of its operations, and exceedingly 
weaken or totally destroy its confidence in its own 
conclusions ; and thus the mind is kept in a distress- 
ing state of incertitude and perplexity and conscien- 
tious doubt, which only increase the insane energy of 
the moral sense. And in this manner the keenest 
and most excruciating excess of human misery is fre- 
quently produced. 

617* In all cases when a morbid nervous irritation 
and sensibility attend the exercises of the moral sense, 
the diseased nervous sensibility becomes identified, 
in the mental consciousness, with the moral sense 
(305, 565), and thus increases the unhealthy energ^y 
of its influence upon the understanding, and propor- 
tionately increases, in the estimation of the mind, the 
importance of the subject in reference to which the 
moral sense is excited (576). 

618. Having thus ascertained the precise nature 
and power of the moral sense and of the conscience, 
and to what extent a want of perfect integrity in the 
moral sense is conducive to an erroneous or unsound 
conscience, I proceed to the consideration of other 
sources of a false conscience. 

619. We have seen (612) that the moral sense ever 
and only says, ' be right ! be right !* and has in itself 
no power to determine what right is, but depends en- 
tirely on the understanding to ascertain what is right ; 
and whatever the understanding fully determines to 
be right, when acting under the influence of the moral 
sense, the moral sense necessarily receives and enforces 
as right. If, therefore, by any means, the under, 
standing is fully brought to an erroneous conclusion 
on any moral or religious subject, the conscience on 
that subject necessarily becomes fallacious. Now there 
are several sources of erroneous conclusion in the un- 
derstanding besides those which I have already named. 
Much has been said about intuitive knowledge, but I 
apprehend there is very little meaning in the term. 
£xcept in the perception of our simple ideas, there is 
always necessarily more or less of reasoning in every 
operation and exercise of the mind (546). The un. 
derstanding, therefore, always arrives at its conclusions 
much as a jury arrive at their verdict. When any 
subject or proposition is brought before the mind, there 
must be some evidences for or against the truth of the 
proposition, and perhaps both. It is the business of 
the intellectual faculties to examine these evidences 
with proper care, and to come to a conclusion in the 
affirmiltive or negative of the proposition according to 
the true force or weight of evidence in the case. But 
if the true evidence m the case be neglected, or but 
liffhtly and carelessly considered, or if but a small part 
of the true evidence in the case be examined, or if the 
evidence be unfairly presented, or if false evidence be 
presented as true, the understanding, even under the 
promptings of the moral sense, may come to erroneous 
conclusions, and fully determine that to be true or 
right which is not really so, and thus a fallacious con- 
science wiU be formed. 

620. Furthermore, we have seen (565, 595), that 
the intellectual faculties are constitutionally and inti- 
mately associated with the natural instincts, propen. 
sities, and appetites of the body ; and that the thou- 
sands of artificial wants, propensities, and appetites, 
which are ingrafted upon the natural instincts and 
sensibilities of the body, act upon the intellectual 
faculties in precisely the same manner as the natural 
instincts and propensities do, but with more vehem- 
ence and despotism (598). We have seen also, that 
it is a general law, common to man and the lower 



animalg, that the mental and voluntary powers always 
naturally obey the bodily propensities and appetites 
(ft96, 697)* and seek to supply the bodily wants. 
Hence all the carnal influences of the human body, 
and especially those which result from the deprava- 
tion of the natural instincts and sensibilities (598), 
such as every lust for every kind of intoxicating and 
every stimulating drink and substance, and every 
appetite and desire ingrafted upon the body, or grow, 
ing out of the artificial habits and circumstances of 
society, are directly adverse to correct perceptions, 
reasonings, and conclusions of the mind on all moral 
and religious subjects ; and, therefore, it is a general 
law, that the ability of the understanding to ascertain 
moral and religious truth, in view of facts and evi. 
dences presented and accessible to it, alwavs corre- 
sponds with the phvsiological and moral purity of the 
individual (007). ^hus : suppose a man to be strongly 
addicted to the use of tobacco, and suppose we should 
attempt to convince that man that it is morally and 
naturally wrong to chew tobacco, or use it in any way 
as a means of sensual gratification. Now, in the first 
place, that man's tobacco has impaired the delicacy 
of his moral sense (615). In the second place, it has 
in some degree impaired the nice powers of the under, 
standing to perceive moral truth (599). In the third 
place, it has established in the physiological economy 
of his body, an appetite whose deitpotic and often irre- 
sistible influence upon the intellectual and voluntary 
powers, vehemently urges and even absolutely com. 
pels the understanding and will to comply with its 
demands (.598) . When, therefore, we attempt to con- 
'vince him that it is morally and naturally wrong for 
him to use tobacco, we shall in the flrst place find it 
extremely difficult to reach his moral sense through 
the opposing energy of his lust. In the second place, 
his lust will not suffer his mind to fix its attention 
seriously and earnestly on the evidence which we pre- 
sent, but will keep it constantly employed in contem. 
plating the importance of the gratification to his hap. 
piness, or in seeking for arguments to defend the 
gratification, or for evasions and subterfuges from 
the fi>rce of our evidence. In the third place, if we 
succeed in rousing his moral sense, and fixing his 
attention, and forcing our evidence upon him, his lust 
will not suffer his understanding to weigh that evi. 
dence with impartiality and honesty, but will compel 
him to weigh it in unequal scales, like one who weighs 
the gold he receives in a pair of iron scales with a 
powerful magnet lying concealed under the scale 
which contains his weights, and drawing it down 
with such a force as to make the gold appear of no 
weight at all. His lust will not suffer him to measure 
our evidence by any standard of truth, but force him 
to measure it by his own despotic and vehement 
energy, and thus make it appear as nothing. Or if 
we happen to approach him at a moment when his 
lust is slumbering in the stupefaction of a recent de. 
bauch, or if by any means we can for a moment suc- 
ceed in silencing his lust, and by the assistance of 
his excited moral sense and the force of our evidence 
turn the balance of his understanding in favor of 
truth, and convince him that it is wrong for him to 
use tobacco, scarcely shall we cease to urge our evi. 
dence directly upon his attention, before his reviving 
lust will rise up with clamorous and impetuous im. 
portunity, or irresistible imperiousness, and bring 
his undersUnding to the f\ill conclusion that it is not 
morally wrong for him to use tobacco ; and thus he 
will establish a fitUadous conscience, and return like 
a swine to the mire, and like a dog to his vomit. In 
this manner, every lust and appetite, natural and in- 
grafted (598), according to the energy of iu influence 
on the intellectual and voluntary powers, tends to 
produce erroneous conclusions in the understanding, 
and thus produce an unsound or fallacioat eonscienoe. 
621. We find, therefore, that the carnal influence 

of the human body on the intellectual and moral 
powers (604), is the grand primary source of errone- 
ous conclusions and of a fallacious conscience. And 
this important and incontrovertible principle in men- 
tal and moral phvsiolo^^y is explicitly and fully asserted 
by the apostle l^aul, in his Epistle to the Hebrews. 
He exhorts the Hebrew proselytes to Christianity to 
prepare themselves to contemplate and understand 
and receive and love and obey the simple and pure 
and sublime doctrines of the Gospel, by having their 
hearts sprinkled from an evil or unsound conscience ; 
or, by being cleansed from all those lusts and appe- 
tites and prejudices which have led their understand- 
ings to erroneous conclusions, and thus established 
an unsound conscience in them, and unfitted them to 
receive the Gospel in all its naked and beautiful sim- 
plicity of truth. 

622. If, therefore, by any means, the understand, 
ing, under the promptings of the moral sense, is 
brought to an erroneous conclusion, and fully deter, 
mines that to be true or right which is really errone- 
ous or wrong, the moral sense necessarily receives it 
as true or right, and prompts the soul to obey it as 
right, and thus man acts conscientiously wrong. 
And this is what Jesus meant when, seeing the Jews 
acting with great zeal conscientiously wrong, he said 
to them, * If your eye be unsound, your whole body 
is full of darkness.* When an unsound or fallacious 
conscience is once established, it is next to impossible 
to remove it, especially in any matter which relates 
to the carnal propensities and appetites. Because 
the moral sense has in itself no means of testing the 
soundness of the conscience, and no way of removing 
an unsound conscience, but by the correct operations 
and conclusions of the understanding ; and the un. 
sound conscience being the advocate of the carnal 
propensities and appetites which begot it, quiets the 
moral sense, and prevents its acting on the under, 
standing to excite it to a new examination of evidence, 
and to bring it to new conclusions; and therefore 
man has, in himself, no disposition to reject that as 
erroneous and wrong, which he conscientiously be. 
lieves to be true and right ; and if others attempt to 
convince him that it is wrong, his unsound conscience 
instantly interposes itself between such attempts and 
his moral sense, and keeps that quiet, while his carnal 
lusts rise up to prevent the mind from attending to 
the evidence presented, or to force the understanding 
to weigh the evidence in unequal scales ; and all the 
while they justify themselves by the unsound consci- 
ence which is their offspring : and hence, as a general 
rule, it is impossible by any means to remove an un. 
sound conscience until the carnal lusts and inordinate 
appetites and prejudices are subdued. And it was 
in view of this great difficulty of removing an unsound* 
conscience, and of the great evils to which such a 
conscience leads, that Jesus declared to the deluded 
Jews, 'If, therefore, the light which is in you be 
darkness, how great is that darkness !* 

623. Now, as the condition of the intellectual and 
moral faculties, and the power of the mind to ascer- 
tain the truth, and especially moral and religious 
truth, greatly depend, as we have seen (620), on the 
conditions of the bodily organ ; therefore, whatever 
increases the influences of the propensities, desires, 
and appetites of the body (607), on the intellectual 
and moral faculties, beyond the real and true wants 
of the human system, not only depraves the organs, 
and leads to all the forms of bodily disease and suffer- 
ing, and to premature death, but also necessarily im- 
pairs the intellectual and moral faculties, stupefies 
the moral sense, blunts the perceptive and reflective 
powers of the mind, and renders man less and less 
capable of perceiving and appreciating moral and 
religious truth, and of being acted on by any other 
than sensual motives. Hence the Scriptures declare 
that the animai man receiveth not the things of the- 



spirit of God, because they are insipid or of no force 
to him ; his moral susceptibilities are not adapted to 
them ; and therefore he cannot know them, because 
they are spiritually discerned. And it is a gross 
state of sensuality, and consequent intellectual and 
moral stupidity and darkness, which the Scriptures 
signify when they say, * The heart of this people is 
waxed fat or gross, and their ears are dull of hearing, 
and their eyes have they closed, lest they should see 
with their eyes, and hear with their ears, and under- 
stand with their heart, and should be converted, and 
I should heal them.' Hence the New Testament is 
replete with passages affirming the intimate relation 
between the carnal influences and the moral charac- 
ter of man, and earnestly exhorting and entreating 
believing Christians to crucify the flesh with the lust 
thereof ; to walk not after the flesh ; to suffer not 
sin to reign in the mortal body by obeying the lusts 
thereof; to keep under the body and bring it into 
subjection ; to present it a living sacrifice, holy, ac 
ceptable to God ; to render it a temple of the Holy 
Spirit, even of the living God. Because the flesh 
Insteth against the spirit, and the spirit against the 
flesh ; and the minding of the flesh is death, because 
of sin, or the transgression of the constitutional laws 
of the animal, intellectual, and moral nature of man : 
but the minding of the spirit of truth is life and 
peace, because of riefhteousness, or the obedience of 
those constitutional laws : and consequently, he that 
soweth to the flesh, shall of the flesh reap corruption ; 
but he that soweth to the spirit, shall of the spirit 
reap life everlasting. And therefore godliness, or 
the strict obedience of the laws which God has con- 
stitutionally established in the animal, intellectual, 
and moral nature of man, is profitable or serviceable 
to all, having the promise of the life which now is, 
and of that which is to come. 

624. The moral faculties being constitutionally in- 
herent in human nature, man is therefore necessarily 
a religious animal; but there is no constitutional 
necessity nor certainty that his religion will be the 
religion of truth. We have seen (603), that the cor- 
poreal nature of man holds, in common with all ma- 
terial forms and substances, a fixed constitutional re- 
lation to God as its intelligent and omnipotent first 
and continually efficient Cause, and that the moral 
nature of man holds a fixed constitutional relation to 
the moral character of God, as a moral Governor, 
Judge, and Father ; and that the constitutional laws 
of man's moral nature perfectly harmonize with the 
constitutional laws of his animal nature, so that the 
perfect fulfilment of the one requires the perfect ful- 
filment of the other, and the violation of the one is 
necessarily attended with an infraction of the other ; 
and furthermore, that the moral and religious instruc- 
tlons of the Gospel of Jesus Christ perfectly harmo- 
nize with the constitutional laws of man's moral and 
animal nature. True religion consists then in per- 
fectly obeying all the constitutional laws of human 
nature ; for this would be fulfilling our twofold re- 
lation to God, our duty to ourselves and our relations 
to our fellow creatures : and thus we should love God 
with all the heart, soul, mind, and strength, and our 
f(^ow creatures as ourselves. But human nature 
has always come short of this perfect fulfilment, and 
from the delinquency has sprung all the natural and 
moral evils that man experiences in this world. And 
the Gospel affirms that man has thus failed through 
the weakness of the flesh, and therefore that God 
has established an economy of grace, in which he will 
accept the true and sincere spirit to do, though man, 
in the frailty of his nature, comes short of the perfect 
fulfilment of law. But this economy of grace does 
not save man in the present state of being, from the 
penalties which must necessarily result from the vio- 
lations of the constitutional laws of his animal nature. 

625. If from inattention to true evidence (619) or 

want of information, from sensuality (620), or any 
other cause, the understanding remains unenlightened 
and undecided under the promptings of the moral 
sense (612), the mind is thrown into a state of painful 
perplexity, and not perceiving distinctly where the 
truth lies, and still fearing lest it should not embrace 
erery point in which it may lie, it is led to give im- 
portance to things in themselves wholly unimportant, 
even to the extent, in some cases, of making an ob- 
ject of worship of a lifeless image or of a ' four-footed 
beast or creeping thing.* This is superstition'. 
If through the power of the carnal influences, or any 
other cause (620), the mind is led to lay hold of erro- 
neous evidences, or inaccurately weigh the true evi- 
dence presented to it, and thus the understanding is 
fully brought to erroneous conclusions, under the in- 
fluence of the moral sense (622), these conclusions 
will constitute a false conscience ; and on these con* 
elusions man builds the superstructure of his future 
interests and hopes, and with such associations they 
become of the utmost importance to his feelings, and 
he consequently regards with extreme jealousy every 
thing which seems to militate against them. This is 
BIGOTRY. When the passions become excited in be- 
half of these conscientious errors, man often pursues 
them with the utmost exercise of all his energies, and 
perhaps accomplishes more evil in the pursuit, and 
performs more deeds of horror, than under any other 
cause of action. This is fanaticism. Yet in all 
this error, the moral sense speaks but one thing : ' be 
right ! be right ! * The evil therefore lies in the 
errors of the understanding, and the errors of the 
understanding arise mainly if not entirely on moral 
and religious subjects, from the influences of the car- 
nal nature. 

626. According, then, as man uses the powers and 
means which he possesses, and which lie within the 
reach of his capabilities, so will his religion be true 
or false. If true, it will lead to his highest and best 
condition. If false, it leads to his greatest evil. But 
whether his religion be that of truth unto good, or of 
error unto evil, man must be religious, or cease to be 
what he constitutionally is ! His religion may indeed 
be nothing but the most savage and degrading super- 
stition and idolatry ; or, if possible, it may be of a 
still lower and more brutal order than this ; or it may 
run into the most atheistical ly religious fanaticism 
against religion ! but still, ransack the earth and 
ocean, and wherever you find a human being who is 
not an idiot, however savage his condition, however 
low his state, if vou are capable of studying man, 
you may find in him the constitutional rudiments of 
a moral and religious character. 

627. If man, therefore, be not led to the religion of 
truth, and thus exalted to his highest and best condi- 
tion, to a holy and happy alliance with his benevolent 
Creator, he will, with inevitable necessity, sink into 
the religion of error, and thus be degraded to wicked, 
ness and misery, in proportion as he departs from the 
truth constitutionally established in his nature. And 
in proportion as the mind becomes darkened, and the 
conscience erroneous, and the moral sense blunted or 
feeble, man becomes less and less capable of ascertain- 
ing moral truth, and of perceiving and understanding 
spiritual things ; and more and more inclined to carnal 
forms and ordinances, and the worship of sensible ob- 
jects, and to the grossest and most degrading idola- 

628. Finally : we see from the views which have 
now been presented, that man has an animal nature, 
endowed with intellectual and moral powers (602) ; 
that his intellectual powers naturally obey the pro- 
pensities, appetites, and desires of his animal nature 
(697), whether originally instinctive ov acquired (598); 
that the grand law of action in the animal nature of 
man is self-indulgence ; that all transgression of the 
constitutional laws of tJie animal nature of man, in 



supplying the natural wants or in gratifying the natu- 
ral propensities, necessarily more or less depraves the 
natural instincts and sensibilities of the body, and 
rapidly generates new wants, new appetites and pro- 
pensities, which act on the intellectual and voluntary 
powers with a much more imperious and despotic en- 
ergy than the natural ones, and always tend to excess, 
and lead to the destruction of the individual and the 
extinction of the species ; that the moral powers are 
established to preside over the operations of the intel- 
lectual faculties, with a determinate reference to the 
constitutional laws and relations of human nature ; 
and therefore that their office is to prompt the mind 
to find out, and the individual to obey, the constitu- 
tional laws and relations of his nature. And in doing 
this, the moral sense cannot in itself tell what is true 
or right, nor has it any ability to tell whether the 
conclusions of the understanding are correct or errone- 
ous. It can only say to the understanding with more 
or less energy and importunity, ' be right! be right I' 
and whatever the understanding fully and confidently 
determines to be right, the moral sense necessarily 
receives and enforces as right ; and this is the con- 
SCIENCE. Therefore, when the conclusions of the 
understanding are strictly true, the conscience is true; 
but if by any means the understanding is fully brought 
to erroneous conclusions under the promptings of the 
moral sense, the conscience is false. And consequent- 
ly, the fact that a man is conscientiously sincere in 
a thing, is no proof that the thing is right ; nor is the 
fact that a man^s conscience does not reprove him in 
what he does, any proof that he is not acting morally 

629. My analysis and philosophy of the moral 
powers thus far, are perfectly reconcileable to the 
views of Gall and Spurzheim, except that they make 
the brain of more exclusive importance than I do 
(588), and attribute much less to the physiological 
and pathological powers and conditions of the nerves 
of organic life and th e organs of relation. They study 
man more exclusively within the brain (592), while I 
insist much more on the physiological laws of his 
whole organization. They may be correct in assert- 
ing that man has other innate moral faculties, such 
ai benevolence, veneration, etc. If there be such 
innate powers, and there is much and strong evidence 
of it, it is entirely certain that the philosophy of them 
in the moral constitution and character of man is pre- 
cisely the same as that which I have now explamed 
of the moral sense (1234). And with Uie appUcation 
of this general physioloncal philosophy to all the 
cerebral organs described by Gall and Spurzheim, I 
should have much less objection to their theory, be- 
cause I believe it would thereby be rendered muc^ 
more consistent with truth, and stripped of its moat 
objectionable features. 


How long man can live— The testimony of Moses and other an- 
cient writers concerning primitive longevity— Primitive compu- 
tation of time— If man ever lived a thousand years, all the stages 
of life must have corresponded in relativelength ; childhood and 

K)Uth, much more protracted, etc.— Physiology cannot tell how 
ng man can live; fhet must determinate it— The Mosaic re- 
cord of nrimitive longevity fipom Adam to Jacob— Causes which 
have Abbreviated the life of man— The great economy of Provi- 
dence by which the physical constitution of man is renovated— 
The successive stages ofsociety-The grand experiment of man- 
kind in regard to the vital power of endurance— The history of 
this experiment from Adam to Noah, and thence downward; 
and the grand result— The lowest point of constitutional power 
—The savage sute not natural to man— Uncertainty of testi- 
mony concerning the experience of man— Anecdote of the two 
ajred witnesses— Great misapprehension of facts— How Ua the 
facts of experience in individuals and nations may be useful to 
physiological science— Physiological science alone can deter- 
mine how man should live— Experimenul fact alone can deter- 
mine how long man can live— The human constitution essenti- 
ally one— If one man can live a hundred years, others may be 
made to— Those of fbeble constitutions often live to much 

greater age than those of powerful constitutions— The present 
capabilities of the human constitutien— Scriptural objections 
answered— But old age is not desirable— Decrepitude and do- 
tage not essential to old age— TouthfUlness, vivacity, health, 
activity, cheerAilness, iisefulness, and enjoyment, may be pre- 
served, and in a good measure carried up to the last hours of 
extreme old age— To live long is not only desirable, but a duty 
—The preservation of youthfulness, vivacity, and cheerfulness, 
a duty— How this may be done. 

630. HAViyo taken a general survey of the anat- 
omy and physiology and pathology of man as an in- 
tellectual and moral animal, and contemplated the 
wonderful complexity and delicacy, and the feaHul 
liabilities of his organic machinery, the question 
which next presents itself for our consideration, is, 
how long can the vital powers of the human constitu- 
tion, through the operation of this assemblage of 
organs, resist the causes which induce disorder and 
death, and maintain their control over the matter 
which composes their organic structure ? 

631. According to the Mosaic history, the first 
generations of the human race lived several hundred 
years, and some individuals attained to nearly a thou- 
sand; and Josephus, who lived in the commencement 
of the Christian era, and who was extensively ac- 
quainted with the writings and traditions then called 
ancient, and 'saw many works entire, of which we 
have now but a few scattered fragments, assures us 
that the tradition of this longevity extended through 
all antiquity.' He assigns as a reason for the great 
longevity of theprimitive generations, that the human 
constitution was then vigorous and fresh from the 
hands of the Creator, and the food of man was then 
fittter for the prolongation of life ; and he affirms that 
all the writers of antiquities, both among the Greeks 
and Barbarians, admit the longevity of the first ages. 
* For even Manetho,' says he, * who wrote the £gyp. 
tian history ; and Berosus, who collected the Chal- 
dean monuments; and Mochus and Hestiaeus, and 
Jerome the Egyptian, and those that composed the 
Phoenician history, all concur in testifying to this 
primitive longevity. Hesiod also, Hecataeus, and Hel- 
lanicus, and Acusilaus: and besides these, Ephorus 
and Nicolaus, relate that the ancients lived a thousand 
years.* Lucretius, the Roman poet, among other Latin 
writers, also asserts the great longevity of the first 
generations of the human race, and says that they wene 
hardy * because the hard earth produced them'; and 

• Theirsinewy limbs were firmly knit and strong. 
Their life was healthy, and their age was long ; 
Returning years still saw them in their prime ; 
They wearied even the wings of measuring time !' 

632. There has been much speculation in modem 
times concerning the len^ of the years spoken of by 
Moses and other early hutorians, in reference to the 
^riod of human life in the primitive ages of the world. 
Uufeland, a distinguished German physician, thinks 
' it has been made to appear in the lughestd^rree pro- 
bable that the year, till the time of Abraham, consis. 
ted only of three months ; that it was afterwards ex- 
tended to eight; and thai^ it was not till the time of 
Joseph that it was.mad^ to consist of twelve. These 
assertions,' he continues, 'are, in a certain degree, 
confirmed by some of the eastern nations, who still 
reckon only three months to the year ; and besides, 
it would appear altogether inexplicable why the life of 
man should have be^ shortened one half, immediately 
after the flood. It would be equally inexplicable why 
the patriarchs did not marry tUl their sixtieth, seven- 
tieth, and even their hundredth year ; but this diffi- 
culty vanishes when we reckon these ages according 
to the before mentioned standard, which will give 
the twentieth or thirtieth year, and consequently the 
same periods at which people marry at present. The 
whole account, therefore, according to this explana- 
tion, assumes a different appearance. The sixteen 
hundred years before the flood will become four hun- 



dred and fourteen, and the nine hundred years which 
Methuselah lived will be reduced to two hundred; 
an age which is not impossible, and to which some 
men, in modern times, have nearly approached.* 

633. The whole argument against the great longev- 
ity of the primitive inhabitants of the earth may be 
resolved to the following syllogism. Man rarely at- 
tains to more than a hundred years, in the present 
age of the world ; nor has he for many centuries past; 
and few even reach seventy years. But man now 
lives nearly or quite as long as the human constitu- 
tion can be made capable of resisting the natural causes 
of its destruction. Therefore, man never attained 
to a much greater age than he now does ; and, conse- 
quently, the accounts of the extraordinary longevity 
of the antediluvians must either be wholly fabulous,, 
or the years which they are said to have lived must 
have consisted of a much shorter period of time than 
the present year. 

634. The whole, then, comes to this : The consti- 
tutional capabilities of man have, from the beginning 
to the present time, always remained very nearly the 
same. But this reasoning appears to be very inconclu- 
sive, and without any foundation in true physiological 
science. A thorough investigation of the conditions 
and laws of organic life (121, et seq,) clearly shows, 
that from the constitutional nature of things, there 
must necessarily be a termination to human existence 
sooner or later; but there is nothing in physiology, 
nor in any other known science, which proves that 
man cannot as well live a thousand years, as fifty. 
The bare facts, then, that man does not liVe a thou- 
sand years, and has not, for many centuries past, con- 
stitute the only foundation for the assertion that he 
cannot live a thousand years, and therefore that he 
never did live a thousand years. From all we know, 
however, of the laws of fife in connexion with the 
organized matter of the human body, we have not the 
least physiological reason for believing that those con- 
ditions and operations of living organs on which the 
continuance of life depends (133), may not be sus- 
tained, in a possible state of the human constitution, 
for many hundred years. But if there ever was such 
a state of the human constitution, that state necessa- 
rily ihvolved a general keeping of parts, or har- 
mony of proportions or relative conditions. The vital 
processes were much less rapid and intense, and much 
more complete, than at present; the devdopment of 
the body was much slower, and the organization much 
more perfect; childhood and adolescence were propor- 
tionately protracted ; and the change from youth to 
manhood took place at a much greater remove from 
birth ; and boys were lads at thirty, and young men 
marriageable at seventy or a hundred years of age. 
The descent from such an elevated state of the human 
constitution to the common level of the human race 
since the time of Moses, would necessarily be more or 
less rapid and precipitate, according as the habits of 
mankind Were more or less conformable to, or in vio- 
ation of, the laws of life. 

635. But while, on the one hand, physiological 
science affords us no proof that man cannot live a 
thousand years, neither does it on the other hand, 
afford us any proof that he can live even ten years. 
Facts and testimony, therefore, constitute our only 
authority on this point; and although, as I have shown 
(631^, the tradition of the great longevity of the primi- 
tive inhabitants of the earth ran through all antiquity, 
and is asserted by all the Greek and Barbarian histo- 
rians who, two thousand years ago, wrote what was 
then called the ancient history of the human race, yet 
the Sacred Books written by Moses are unquestionably 
the most ancient and perhaps the <mly authentic tes- 
timony which has come down to us on this interesting 
subject. And according to the Mosiac record, Adam 
lived 930 years— Seth, 912— Enos, 905— Cainan, 910 
— Mahalaleel, 895— Jared, 962— Enoch, 365— Methu- 

selah, 969 — Lamech, 777— Noah, 950 — Shem, 600— 
Arphaxpad, 43a— Salah, 433— Ebes, 464— Peleg, 239 
— Reu, 239— Serug, 230— Nahor, 148— Terah, 205— 
Abraham, 175 — Isaac, 180— Jacob, 147. The period 
signified by the word year, in this record, appears to 
mean precisely the same length of time when applied 
to Adam and Methuselah that it does when applied to 
Abraham, Isaac, and Jacob ; or in other words, Moses 
appears to have used the Hebrew term which is ren- 
dered * year ' in our English Bible, for precisely the 
same length of time when speaking of the age of the 
antediluvians, and when speaking of that of the post- 
diluvians. And, therefore, if we are to understand 
from the Mosaic record that Methuselah lived but 242 
of our years, then the patriarch Jacob lived but 37 
years. It is highly probable, however, that the aver- 
age period of life of the individuals named by Moses, 
from the creation to the flood, is considerably greater 
than the average period of human life in the whole 
species during the same time. Nor is the rapid abbre- 
viation of the period of human existence after the 
flood by any means inexplicable or marvellous, even 
if it be admitted that Noah actually lived 950 of our 
years. It is, indeed, no uncommon thing to meet with 
facts perfectly analogous in our own times. 

636. Whatever may be true, however, as to the pre- 
cise length of the period of human existence before 
the flood, it cannot reasonably be doubted that the 
primitive generations of mankind very greatly exceeded 
in length of life the present inhabitants of the earth. 
Nevertheless, it appears very evident that, for the last 
three thousand years, the general average of human 
life has remained pretty nearly the same. 

637. How far the changes which have taken place 
in the earth and its atmosphere may have been con- 
cerned in the abbreviation of human life, cannot be 
known. It is probable that such changes have at 
times affected animal life very generally and with great 
power, as epidemic causes of disease and death ; but 
there is no reason to believe that any permanent con- 
stitutional change has taken place in the atmosphere, 
nor any change in the condition of the earth, by which 
the human constitution has been permanently im- 
paired to any considerable extent. Nor is there reason 
to believe that any thing more than natural causes 
have operated to produce whatever changes have taken 
place in regard to the longevity and general condition 
of the human race ; and among these, the most power- 
ful are unquestionably those which are connected 
with human agency, and within the control of human 

638. The whole history of the human race fully 
proves that man is so constituted as an intellectual 
and moral animal, that those excesses which deprave 
and deteriorate his nature as an individual (599), and 
lead to his individual destruction, and to the degene- 
racy of the human constitution, and the extermination 
of the species, inevitably so affect him in his social 
and political capacities and relations, as that, while 
they impair all the energies of the human constitu- 
tion, and fit man to be the progenitor of a still more 
degenerate progeny, and thus gradually lead to the 
extermination of the race, at the same time so impair 
the energies of his intellectual and moral powers, so 
ingulf his social and civil virtues in selfishness and 
sensuality, as to render him incapable of sustaining 
those social and civil institutions and political condi- 
tions by which he is protected in his degenerating 
luxuries and excesses, and fit him to become an easy 
prey to the hardier and more warlike portions of his 
race, or to sink by a general decay of state and civil 
feuds, into an equally degraded condition of vassalage 
or slavery or barbarian rudeness, in which, with the 
loss of science and literature, and all the elegant re- 
finements of civic life, he is also stripped of those luxu- 
ries, and compelled to forego many if not all of those 
enervating and deteriorating habits and circumstances 



by which his whole nature has been reduced to the 
very brink of utter destruction ; and thus, like the 
king of Babylon, he is driven forth from the excesses 
of his voluptuousness and general sensuality, and 
forced to subsist in the simplest and rudest manner, 
in a state of little more than animal existence. From 
this state he slowly rises by the gradual cultivation of 
his intellectual and moral powers, and of the social 
and civil virtues, till, with renovated physical ener- 
gies and constitutional powers, he attains to what is 
universally called the golden age, in which all the 
circumstances of his existence seem to be best adapted 
to human health and longevity and virtue and happi. 
ness. To this generally succeeds the age of heroism 
and conquest, and then follows the age of stern and 
noble patriotism, and legislative wisdom, and political 
energy and power. The age of wealth comes next, 
and with it brings the age of luxury and refined sen- 
suality and excess. Multiplying Disease rahes its ad- 
monishing voice in vain, restilence peals a louder 
and more terrific note of rebuke ; and man, in the 
moment of dismay, at first refrains from his excesses, 
and affords his constitution an opportunity to gather 
up some of its prostrated energies. But his partial 
reformation too often proves to be only a preparation 
for greater excesses than before, and he rusnes onward 
in the current of indulgence, till even the terrible re- 
bukes and chastisements of pestilence seem only to 
harden him and increase his temerity, until he revels 
in maniac sensuality even in the lazaretto, and yields 
to the fierceness of his beastly lust upon the very 
threshold of the chamel house. In this fearful man- 
ner the nations of the earth have been scourged, till 
it seemed as if the human race would be wholly ex- 
terminated ; and only by such severe and awful re- 
tributions from the violated laws of nature, have 
mankind been induced to pause from their sensual 
excesses, and investigate even the most obvious rela- 
tions between their habits and their sufferings. Nor 
has all this been sufficient so to restrain them in their 
downward course, as to prevent the necessity for those 
mighty revolutions which, from the banning, have 
continued to roll up barbarian hordes to the zenith of 
civilization and luxury, and to roll down civilized and 
refined nations to the nadir of barbarian darkness. 
And thus the human constitution has, from time to 
time, been partially renovated, and the human race 
perpetuated, by the very means which have often al- 
most blotted the intellectual and moral man from the 
face of the earth ! 

639. Indeed it seems as if the grand experiment of 
mankind had ever been to ascertain how far they can 
transgress the laws of life, how near they can approach 
to the very point of death, and yet not die, at least so 
suddenly and violently as to be compelled to know 
that they have destroyed themselves. 

640. The primitive inhabitants of the earth, having 
once broken away from the simplicity and truth of 
nature, and begun to acquire artificial appetites of far 
more despotic power (598^ than nature^s noly instincts, 
rushed forward to new indulgences with increasing 
eagerness and celerity, and plunged downward to 
deeper and yet deeper sensuality, impelled by a con- 
tinually accumulating moral force arising from their 
more and more depraved and more vehement and ty- 
rannous propensities, till the horrible enormities of 
human wickedness rose up to heaven, and God, in 
very mercy, quenched the bursting volcano of human 
passions by the flood, and almost entirely extermin- 
ated the hunily of man, to save the earth from a 
bloodier deluge and a darker desolation, and man 
from a more violent and cruel end. And when the 
earth rose from her deep baptism, sanctified from the 
pollutions of a drowned race, the renmant of that race 
which Ood had saved for the perpetuation of the 
human kind, came forth with appetites unsanctified 
by the terrible ablution of the world, to commence 

anew the downward and ruinous career of sensual ex- 
cess. And surely, if the patriarchal father who, of 
all the earth *s inhabitants, was most virtuous and 
most acceptable to God, brought with him from be- 
yond the flood an appetite which, in spite of the awfiil 
judgment he had seen inflicted on a sinful world, led 
him to the excess of most disgraceful drunkenness, as 
soon as he could procure the means, it cannot be sup. 
posed that, with such an example and such oppor. 
tunities before them, the sons of that patriarch, born 
and reared as they had been, amidst the fiercest ex- 
cesses of the old world's sensuality and violence, were 
more abstemiously and virtuously inclined than was 
their aged sire. 

641. It is not strange, therefore, that their lives 
were much abbreviated by their excesses (635), nor 
that the succeeding generations of mankind, pursuing 
the same downward career of sensuality, should suffer 
a continual abbreviation of the period of their exist- 
ence, till repeated calamities had forced them to ascer- 
tain the lowest point to which they could descend 
without exterminating the human species. 

642. From that time to the present, mankind have 
revolved around the minimum point of constitutional 
power, in the circle which I have described (638), 
from savage to civilized life and luxury and every 
deteriorating excess; and from this, to savage lire 
again ; and thence slowly rising to the golden age, 
and then again declining. And consequently, though 
in these succeeding revolutions, the succeeding na- 
tions of the earth have had their elevation and de- 
clension, yet the average level of human life has been 
nearly the same for the last three or four thousand 
years. Each nation has had its period of longevity, 
its age of heroism, conquest, patriotism, legislative 
wisdom, political energy, wealth, luxury, etc. It is 
also true that the general average of life often runs 
low in a nation which at the same time has many 
instances of individual longevity ; and on the other 
hand, the average period may be considerably elevated 
when there are few remarkable cases of individuals 
who attain to very old age. Both of these facts may 
easily be explained on the plainest principles of physi- 
ological philosophy. But were I to follow out all the 
leadinp of this interesting subject, the extent of my 
investigations would necessarily fietr exceed the bounds 
which I have set for myself on this topic of inquiry. 

643. The lowest point of constitutional power by 
which the human species can be preserved, is that 
which will sustain a sufficient number of each gene- 
ration long^ enough in life to become the progenitors 
and nurturing protectors of another generation. When 
it falls short of this, the human race tends rapidly to 
extinction ; and in this manner, particular finmilies are 
very frequently exterminated, and even whole tribes 
are sometimes cut off. But as we have seen (638), a 
wise and benevolent Creator has so constituted things, 
that the human species as a whole are not permitted 
to go beyond certain limits, without falling into Uiat 
condition in which intellectual elevation, science, lit- 
erature, and all the elegant refinements and deteri- 
orating luxuries of civic life, are sacrificed for the 
physical renovation of human nature. Yet if by any 
means the human race can be kept sufficiently above 
the minimum point of constitutional power, the species 
can be preserved without the renovating process of 
which I have spoken, or without a recurrence to the 
severe simplicity and privations of the savage state. 
Be it remembered, however (25, Note), I do not affirm 
that the savage state is best adapted to human health 
and longevity, but that this state of severe privation 
and rudeness has hitherto been necessary to strip man 
of the means of luxury and excess, and thus afford 
his constitutional powers an opportunity to recover in 
some degree their impaired energies, 't'et the savage 
state is generally attended with many circumstances 
which are decidedly unfavorable to health and Ion- 



gevity, and often with extreme violations of the laws 
of life. 

644. "Well regulated civilized life is, therefore, un- 

Suestionably best adapted to the full development of 
tie physical and intellectual and moral capabilities of 
man ; and it is a necessary truth established in the 
constitutional nature of things, that not only individ- 
ual health and happiness and prosperity, but also the 
political prosperity and durability of nations are, as a 
general statement, always proportionate to the degree 
of conformity of the people to the laws of life. 

645. To ascertain what those causes are by which 
the period of human existence is abbreviated, and by 
what means we may with greatest certainty not only 
secure the longest life, but also the highest degree of 
health and the greatest amount of happiness, consis- 
tently with those principles on which our highest in- 
tellectual and moral good depends, must necessarily 
be regarded by all truly rational creatures as of the 
utmost importance. 

C46. In pursuing this investigation, however, we 
meet with many and ^reat difficulties ; not from any 
uncertainty of physiological principles, but from the 
almost impossibility ofascertaining real facts, because 
we are obliged, to a very considerable extent, to take 
the testimony of others in regard to things which we 
have not the opportunity to examine for ourselves. 
And unfortunately for the human race, too many that 
have been considered valid sources of information, have 
only served to mislead mankind, and to establish those 
erroneous opinions from which have sprung some of 
the most pernicious practices which have afflicted our 

647. We have been told that some men enjoy health 
and live to great age in warm and in hot climates, and 
that others enjoy health and live to great age in cold 
climates (15) ; some on one kind of diet, and some on 
another ; some under one set of circumstances, and 
some under another; therefore, what is best for one 
man, is not for another ; what agrees toell with one, 
disagrees with another ; what is one man*s meat, is 
anoUier man's poison ; different constitutions require 
different treatment; and, consequently, no general 
rules can be laid down, which are adapted to every 
man in all circumstances, and which can with propri- 
ety be made the laws of regimen to all. . 

648. These erroneous dogmas, so far as the world 
is now informed, were first advanced by Hipprocrates, 
and with all servility have been handed down from 
generation to generation, till they have become the 
CiHnmon sentiments of mankind, which he who ques- 
tions, will incur the charge of rashly contradicting 
the common sense and universal experience of the 
human family* And hence, the common mode of 
reasoning on this important subject is necessarily and 
exceedingly erroneous; and nevermore so than when 
it is supposed to be truly and rigidly inductive. 

649. Among the numerous illustrations of the truth 
of the common notions which I have just stated, the 
anecdote of the two aged witnesses who appeared be- 
fore the civil magistrate, is often repeated by those 
who are willing to observe no other rules of life than 
the leadings of their appetites. It is said that on a 
certain occasion, there appeared before a civil magis- 
trate a very aged witness, who possessed so much 
bodily vigor and elasticity, and retained his mental 
and moral faculties so remarkably, as to attract the 
particular attention of the court ; and when the trial 
was closed, the magistrate asked him how old he was ? 
' The days of my pilgrimage are a hundred vears, may 
it please your honor,' was the old man's reply. ' And 
by what means,' inquired the magistrate, ' have you 
reached such an advanced period of life, and retained 
all your faculties and powers so well ?' 'May it please 
your honor,' the old man replied, 'I was bom of 
healthy parents, and from my youth up have led a 
regular and temperate life. My food has been simple 

and plain, my drink has been water, I have retired to 
rest in good season, and risen early ; I have been care- 
ful to govern my passions, and to preserve a great 
serenity and uniformity of mind and habit. In short, 
I have been always systematically regular and tem- 
perate in all things.' Pleased with the old man's ap- 
pearance and his history, the magistrate embraced 
the occasion to expatiate on the virtues of temperance 
and ^ood habits, and to exhort the numerous audience 
to follow the example of this 'green old man.' Soon 
after this, another aged witness appeared before the 
same magistrate, who was equally remarkable for his 
bodily health and vigor, and for the soundness and 
energy of his mental and moral powers. He also was 
asked by the magistrate how old he was, and by what 
means he had preserved his life and health and all 
his faculties in so vigorous a state ? ' May it please 
hour honor,' said the aged witness, ' I am a hundred 
years old. I have taken no pains to preserve my life 
or health. I have followed no rules, but have led an 
irregular life. I have always indulged my appetite 
in just what it craved; I have eaten what I wanted, 
when I chose, and as much as I desired ; and my food 
has generally been rich and savory. I have always 
drunk wine, beer, and ardent spirit, freely, and often 
to great excess. In short, I have lived just as it hap- 
pened, and am now living and well as your honor sees 
me, because my life and health have been continued 
to me, and not because I have taken any pains to pre- 
serve them.' The magistrate was exceedingly con- 
founded by this man's statement, and only remarked 
that he perceived that some men would attainjto old 
age In one way, and some in another. 

650. Those who repeat this fabulous anecdote, seem 
to think that it is a true narration of facts, and that 
it fully proves the entire futility of all rules for the 
preservation of life and health, and completely de- 
monstrates that a vigorous old age is attained to with 
as much certainty in one way as in another. But, 
in the first place, this story bears the evidence of fic- 
tion and of falsehood on its very face ; for although it 
is possible that a man of remarkably powerful con- 
stitution may live till he is a hundred years old, and 
retain his faculties and powers in considerable vigor, 
whose habits hare been such as the seoond witness in 
this story is made to declare his own to have been, 
yet it is not possible for two persons, with an equally 
excellent onginal constitution, to reach a hundred 
years, with habits of life so different as those stated 
of the two witnesses in this story, without the most 
marked and manifest difference of appearance and 
condition of body and mind ; and a difference, too, 
which would afford the strongest evidence in favor of 
a temperate and regular life. Therefore, in the 
second place, if this story were true, it would afford 
no evidence in favor of the position which it is in- 
tended to establish, but would simply go to show that 
the first witness, with an ordinary or perhaps feeble 
constitution, had by virtue of correct habits attained 
to a remarkably healthy and sound old age ; while 
the second witness had reached the same age with 
equal health and vigor, in spite of exceedingly bad 
habits, by virtue of a most extraordinarily powerful 

651. Yet, without taking the pains to examine all 
the circumstances of the case, most people consider 
the bare fact that some intemperate and irregular 
individuals reach a vigorous old age, a conclusive 
evidence that such habits are not unfavorable to long 
life; or that a man of intemperate and irregular 
habits is just as certain of reaching a hundred years, 
as one of the most temperate and regular habits is ; 
and therefore almost every body has a demonstration 
of this kind in the history of some kinsman or neigh- 
bor or acquaintance, or somebody else. And with 
the same loose kind of inductive reasoning, people 
arrive at conclusions equally erroneous, in regard to 



tribes and nations. If a tribe or nation which sub- 
sists on vegetable food is weak, slugfi^sh, and destitute 
of courage and manly enterprise, it is at once con- 
cluded that vegetable'food is the cause ; and the gene- 
ral proposition is laid down that an exclusively vege- 
table diet is not favorable to bodily strength and 
activity, and mental vigor and sprightliness. Yet a 
proper examination of the subject might have shown 
that other causes fully adequate to these effects ex- 
isted in the condition and habits of that tribe or na- 
tion, which not only exonerated the vegetable diet 
from this charge, but even made it appear that the 
vegetable diet had a powerfully conservative and re- 
deeming effect, and was the principal means by which 
the tribe or nation was saved from a much worse phy- 
sical, mental, and moral condition. 

652. Again, if savage tribes or nations are unpro- 
lific, feeble, sickly, and short-lived, it is at once con- 
eluded that the naturalness and simplicity of savage 
life are unfavorable to bodily development and vigor 
and health and longevity. Yet a proper examination 
of the subject might have shown that causes existed 
in the habits of such tribes or nations, not at all es- 
sential to savage life, and directly opposed to true 
naturalness and simplicity, which were abundantly 
sufficient to account for all the objectionable effects at- 
tributed to savage life (25, Note). 

653. The conclusions, therefore, which are drawn 
from the habits of individuals and of nations, can be 
depended on no farther than they agree with the laws 
of life, ascertained by an accurate and thorough inves- 
tigation of the vital properties of the tissues and func- 
tional powers of the organs, and the general operations 
and results of the vital economy of the human sys- 

654. So far as general agreement exists between all 
cases of remarkable longevity, some respect is to be 
paid to facts ; and these may be adduced as illustra- 
tions of principles otherwise established. But the fact 
that an individual, or a number of individuals, have 
attained to a great age, in certain habits of living, is 
no conclusive evidence that those habits are most con- 
ducive to long life, nor even that they are all favor- 
able to longevity. The only use, therefore, which we 
can safely make of a case of extraordinary old age, is 
to show how long the human constitution is capable 
of sustaining the vital economy, and of resisting the 
causes which induce death. 

655. If we would correctly ascertain how man must 
live in order to secure the most perfect health, and 
attain to the greatest age of which the human consti- 
tution is capable, we must not ransack society to find 
all the remarkable instances of longevity, and learn 
the particular habits of those who have attained to old 
age ; for such a course would only serve to bewilder 
and perplex us, and lead us to conclude that the whole 
question is involved in the most entire uncertainty ; 
because we should find health and old age in almost 
every variety of circumstances in which mankind are 
placed ; and if we were not fully qualified for the se- 
verest and most critical investigation of such an intri- 
cate subject, we should inevitably misapprehend facts, 
and thus be led to erroneous conclusions ; but we must 
study the human constitution with the most rigorous 
scrutiny of science. We must analyze the human 
body to its organic elements (122, 123), and become 
thoroughly acquainted with all the elementary tissues 
(166) which enter into the formation of all its organs, 
and fully understand the peculiar vital properties of 
all those tissues (312), and the functional powers of 
all the organs. We must intimately and accurately 
know all the conditions on which the peculiar proper, 
ties of the tissues and powers of the organs depend, 
and the various causes and circumstances by which 
those properties and powers are favorably or unfavor- 
ably affected. In short, we must ascertain all the 
properties and powers which belong to the living 

animal body, and all the laws of constitution and rela- 
tion appertaining to the vital economy of the human 
system. Here, and only here, can the enlightened 
and truly scientific physiologist take his stand, and 
teach those rules of life by which man may with 
greatest certainty secure the best health, and attain 
to the greatest longevity of which the human consti- 
tution is capable. 

656. But while the truly scientific physiologist, 
from his intimate and thorough know ledge of all the 
properties and powers, and laws of constitution and 
relation, belonging to the human body, instructs us 
how to live in order to secure the highest degree of 
health, and attain to the longest life of which the 
human constitution is capable, he cannot from this 
knowledge tell us what the capabilities of the human 
constitution are in regard to health and longevity. 
He can tell us with accuracy and confidence that sudi 
and such ai^ the laws of lite, and such and such are 
the best means by which health may be secured and 
life prolonged ; but he cannot, from his physiological 
knowledge, tell us whether a strict obedience to the 
laws of life, and a correct use of the best means, will 
prolong our life ten or a thousand years. 

657. If) therefore, we ask the truly enlightened 
physiologist, how we must live to secure Uie best 
health and longest life of which our constitution is 
capable ? his answer must be drawn purely from his 
physiological knowledge ; but if we ask him how long 
the best mode of living will preserve our life ? his re- 
ply is, ' Physiology cannot teach you that. There- 
fore, now go you out into the world, and find the 
oldest man living and enjoying health.* If, after 
having obeyed his command, we return and say to 
him, * we have found several individuals a hundred 
years old, and all enjoying pretty nearly the same 
degree of health, yet they are of very different and 
even of opposite habits:* his answer will be, that 
'probably each of the individuals whom you have 
found has a mixture of good and bad habits, and has 
lived in a mixture of favorable and unfavorable cir- 
cumstances, and that notwithstanding the apparent 
diversity of habits and circumstances among them, 
there is probably a pretty nearly equal amount of 
what is salutary and conservative in the habits and 
circumstances of each and all. Some of them have 
erred in one thing and some in another, and some 
have been correct in one thing and some in another ; 
and therefore the diversity of which you speak is pro- 
bably more apparent than real, in relation to the true 
laws of life. Besides, some, with an extraordinarily 
powerful constitution, may, in the constant violation 
of the laws of life, reach a hundred years, with as 
much health and vigor as others who attain to the 
same period in much better habits and circumstances, 
but with far less powerful constitutions. All that is 
proved, therefore, by instances of great longevity in 
connexion with bad habits and circumstances, is, that 
such individuals possess remarkably powerful consti- 
tutions, which are able to resist for ninety or a hun- 
dred years causes that have in the same time sent 
hundreds of thousands of their fellow creatures, of 
feeble constitutions, to an untimely grave ; and which, 
under a correct regimen, would m all probability 
have sustained life and health a himdred and twenty, 
and perhaps a hundred and fifty years. The only 
use which you can safely make, therefore, of the in- 
stances of great longevity which you have found,* he 
would say, * is to show how long the human consti- 
tation, in the present age of the world and condition 
of the race, is capable of resisting the causes which 
induce death ; and if you have found an individual 
or a number of individuals a hundred years old, it is 
of little importance to you how they have lived ; the 
simple fact that they are a hundred years old is all 
we wish, to prove that the human constitution is now 
capable of reaching a hundred years.* 



658. Physiology, then, alone, can teach us how 
man must uve in order to secure the best health and 
attain to the greatest age of which the human consti- 
tution is capable ; and the fact that there are individ- 
uals now living a hundred years old, proves that the 
human constitution is capable of sustaining life a hun- 
dred years at least, and perhaps much longer, if the 
r^imen and circumstances are in all respects correct. 
But here I shall probably be met with the very an- 
cient and utterly absurd doctrine, that there are dif- 
ferent constitutions, and therefore, that what may be 
true of one, cannot truly be affirmed of all. It is freely 
admitted that, in the present state of the human race, 
spme individuals have more vital energy and constitu- 
tional power to resist the causes of disease and death 
than others have, and therefore, what will break down 
the constitution and destroy the life of some individ- 
uals, may be borne by others a much longer time, 
without any striking manifestations of immediate in- 
jury. It is also true that, in the present state of the 
human race, some individuals have strongly marked 
constitutional idiosyncrasies or peculiarities; but 
these are far more »are and of a much less important 
character than is generally supposed, and in no in- 
stance constitute the slightest exception to the general 
laws of life, nor in any degree interfere with, or mili- 
tate against, the correct principles of a general regi- 
men. ^ Indeed, such peculiarities, though really con- 
stitutional, may in almost every case be overcome en- 
tirely by a correct regimen. I have frequently seen 
the most strongly marked cases completely subdued 
by such means. It is an incontrovertible truth, there- 
fore, that so far as the general laws of life and the 
application of general principles of regimen are consid- 
ered, the human constitution is one ; and there are 
no constitutional differences in the human race which 
will not readily yield to a correct regimen, and by thus 
yielding improve the condition of the individual affec- 
ted; and consequently, there are no constitutional 
differences in the human race which stand in the way 
of adapting one general regimen to the whole family 
of man ; but, on the contrary, it is most strictly true 
that, so far as the general laws of life and the appli- 
cation of general principles of regimen are considered, 
what may be truly affirmed of one man may be truly 
affirmed of all, and what is best for one is best for all; 
and therefore, all general reasonings concerning the 
human constitution, are equally applicable to each 
and every member of the human family, in all ages of 
the World, and in all conditions of the race, and in 
all the various circumstances of individuals. 

659. Now, therefore, if individuals can be found at 
the present time who are a hundred years old, the 
fitct may be adduced as a demonstration that the 
human constitution has vital power enough to resist 
the causes which induce death and to sustain health 
for a hundred years, under whatever disadvantages 
may exist at the present period of the world, distinctly 
from the agency of man. But we know that there are 
many individuals now living and enjoying good health 
in different sections of our country, who are a hun- 
dred years old ; and therefore it may with perfect ac- 
curacy be affirmed, that the human species in the 
United States of America may average a hundred 
years of life. 

660. Is it objected that this is not a legitimate con- 
clusion; that because one man reaches a hundred ye^rs, 
it is no proof that the human species may average 
that length of life ? I ask, by what means has one 
man lived a hundred years ? Will it be affirmed that he 
has been miraculously endowed with vital powers, or 
that his vital energies have from time to time been 
miraculously renovated ? Certainly not ! But it may 
be asserted that he had a remarkably strong consti- 
tution ! This is not always the case. Plato, in his 
Republic, strongly censures Herodicus, one of the pre- 
ceptors of Hippocrates, for teaching the delicate and 

infirm to regulate their exercise and diet in such a 
manner as to prolong their lives for many years, and 
thus attain to old age with a very feeble consti- 
tution. ' He was master of an academy,' says Plato, 
' where youth were taught their exercise, and being 
himself delicate and infirm, he contrived to blend ex- 
ercise with such dietetic rules as preserved his own 
feeble constitution from sinking under his complaints, 
and enabled him to protract his valetudinary existence 
to old age ; and he did the same injury to many others 
of feeble and infirm constitutions.* This Plato calls 
an injury, because he considered an infirm constitu- 
tion an obstacle to the practice of virtue, inasmuch as 
it makes people always imagine themselves ill, and 
causes them to think of nothing but their own infir- 
mities ; and therefore he thought that if a delicate 
person did not soon recover health, he had better die 
out of the way, and not live to be miserable himself, 
and to become the father of feeble children, and thus 
injure society and the ^ ace. Louis Cornaro, a noble 
Venetian, had completely broken down his constitu- 
tion at the age of thirty-five, and had become so infirm 
that he despaired of ever recovering health, or of 
reaching the meridian of life ; yet by greatly reform- 
ing and simplifying his habits of living, he recovered 
health, and lived to be over a hundred years old. 
The venerable Moses Brown, of Providence, R.I., 
now nearly a hundred years old,* and enjoying un- 
common health and activitv for his age, informs me 
that from his birth through the whole of the early 
part of his life, he was exceedingly delicate and feeble, 
and that his constitution has always been very deli- 
cate. He had three brothers, who were all remarka- 
ble for their stout, robust, and vigorous bodies and 
powerful constitutions, yet neither of these brothers 
reached seventy years. At the age of eighty-three, 
Moses Brown observed to a friend, ' I was always a 
feeble frail thing among my brothers, and had no ex- 
pectation of out4iving them ; I am persuaded that if 
I had had the constitution of either of them, and lived 
as I have lived, I should be an active hale man at a 
hundred years old, and should probably live to the age 
of a hundred and ten or a hundred and twenty years 
in good health ; but with my feeble constitution, I do 
not expect to exceed ninety years.' The interesting 
case of this family is by no means an extraordinary 
one. It is no uncommon thing for the most delicate 
member of a family, by a careful regimen and gener- 
ally correct habits, to attain to a very advanced period 
of life, while the more vigorous and hale members, by 
living too fast, are cut off in the middle of life, or per- 
haps in early manhood. I could name a number of 
such instances. 

661. But granting the position, that he who attains 
to a hundred years has a remarkably strong constitu- 
tion; I ask, how the individual came to the possession 
of such a constitution ? Was it the special, direct, and 
extraordinary gift of the Creator ? or was it the natu- 
ral result of a succession and concurrence of causes 
and effects operating in the constitutional nature of 
things ? Most unquestionably the latter ! and these 
causes and effects, as a general law, are perfectly with- 
in the sphere of human agency and under the control 
of human ability. 

662. If by any means, therefore, the human consti- 
tution can be made to resist the causes of death, and 
sustain health a hundred years, in one individual, by 
the same means, the same results can be produced in 
all ; because he who attains to a hundred years, de- 
pends wholly on the intrinsic energies of the human 
constitution, and on those circumstances and habits of 
life which, as a general statement, are under the con- 
trol of human ability. 

663. I do not however affirm, nor intend to imply, 
that the present generation of the human species can 

* Mr. Brown has since died of sicknesss from exposure, in his 
ninety-eighth year. 



by any means all attain to a hundred years of life. I 
know that in the present condition of the race, there 
is a very g^eat inequality of constitutional power. 
Some individuals are bom with constitutions too feeble 
to sustain the functions of life a single year ; others 
have power enough to maintain the victory over the 
causes which induce death for three, five, ten, twenty, 
forty, eighty, a hundred, or a hundred and fifty 
years. Some are born without any strong tendency 
to a particular disease, while others are born with 
the most powerful predisposition to particular disease 
of some kind or other. But it is entirely certain 
that all these constitutional differences result from 
the action of causes which man has the power to con- 
trol ; and therefore it is entirely certain that all these 
constitutional differences can be removed in the course 
of three or four generations of the race, by a strict 
conformity to the laws of life in all the members of 
each generation ; and the human species can be 
brought to at least as great uniformity as to their 
health and length of life, as is found amongst all the 
lower animals in a pure state of nature. 

664. When I affirm that the human species may 
average a hundred years, I do not mean to imply 
that the human constitution is not capable of exceed- 
ing that period. As a physiologist I cannot perceive 
any reason why the human race cannot return to the 
original longevity of the species ; neither can I affirm, 
from any physiological knowledge, that man can live 
a hundred years. The bare fact that the human con- 
stitution does carry some individuals up to this period, 
is all the authority I have for affirming this capability 
of the human constitution ; but this fact by no means 
proves that the capability of the human constitution 
is only equal to a hundred years of life, because it is 
by no means certain that those who attain to the 
greatest age always strictly conform to the laws of 
Ufe ; and therefore, we do not know but that many 
who die at a hundred years, might have reached a 
hundred and fifty years, if in all things they had 
obeyed the laws of life. Besides, were it a known 
truth that in the present state of the human constitu- 
tion, no individual possesses the power to live more 
than a hundred years, this would not prove that in- 
dividuals cannot be produced in the fourth generation 
from the present, with constitutional power to live a 
hundred and fifty or two hundred years ; and I repeat 
that correct physiological science affords no evidence 
that the human constitution is not capable of gra- 
dually returning to the primitive longevity of the 

665. On the whole, then, true physiological science 
alone can teach us how to live, in order to secure the 
best health and attain to the greatest longevity of 
which the human constitution is capable ; and correct 
and continued experiment alone can prove to us how 
long the human constitution can be made to resist 
the causes which induce death (126), and sustain the 
healthful operations of the vital economy. 

666. But I am told that all this reasoning leaves 
God out of sight, and contradicts the sacred scripture 
which affirms that * the days of our years are three- 
score years and ten, and if by reason of strength they 
be four-score years, yet is their strength labor and 
sorrow, for it is soon cut off, and we fly away.' I 
reply that if God had actually and absolutely limited 
human life to seventy or eighty years, then no man 
could possibly exceed eighty years ; but we know 
that many individuals do exceed eighty years of life, 
and that some exceed a hundred ; and, therefore, we 
have a perfect demonstration that God has not abso- 
lutely limited the length of human life to eighty or a 
hundred years, and consequently we know that the 
scripture cited is not the annunciation of a decree of 
God, nor a prophecy, but simply a historical record of 
the fact that at the time when it was written, human 
life rarely exceeded seventy or eighty years, and that 

those who attained to eighty years were extremely 
infirm and helpless, and had little enjoyment of their 
existence. But Isaiah, when speaking prophetically 
of that period in the Gospel dispensation when the 
laws of God shall reign in the hearts and govern the 
actions of mankind, explicitly affirms that the period 
of human life shall be greatly prolonged, and that 
there shall be no more thence an infant of days, nor 
an old man that hath not filled his days^ but their 
days shall be as the days of a tree. 

667. As to my leaving God out of sight, I contend 
that all my reasoning is founded on the fixed laws 
which God has ordained and established in the nature 
of things (110). I acknowledge that God has the 
power to counteract or suspend the laws which he has 
established in the constitutional nature of man, as 
well as those which he has established in the consti- 
tution of the solar system ; and I contend, therefore, 
that it would be just as reasonable to assert that the 
astronomer leaves God out of sight in all his reasonings, 
because he calculates the movements of the heavenly 
bodies according to the fixed laws which God has 
established in nature to govern their movements, as 
it is to raise that objection against the physiologist, 
because he reasons according to those fixed principles 
which God has established in the constitutional nature 
of man. If God has constructed man of such mate- 
rials and upon such principles as render him capable 
of living just one thousand years and no more, by a 
perfect obedience of the laws of life, then God has 
actually set the utmost limits of human life at a thou- 
sand years, and beyond this point no means and no 
conditions can carry us. But if at the same time, 
God has established in our nature such laws of con- 
stitution and relation as that, if man lives in a certain 
manner he can only reach seventy or eighty years, 
then it may be said that God has conditionally limited 
the period of human life to seventy or eighty years ; 
but this conditional lipiitation does not stand \n the 
way of man's prolonging life to the full extent of the 
original capabilities of the human constitution. If it 
is objected that God foreknows or has decreed the 
precise length of every man's life, and no human 
means or conditions can add to or take from that fixed 
period a single hour or second of time, then I reply 
that God has also decreed the precise means and con- 
ditions by which the life of each individual shall be 
carried to its fixed termination ; and God has just as 
certainly decreed the efforts which I make to secure 
human health and to prolong human life, as he has 
decreed the length of any man's life ; and if he has 
decreed that the length of human life shall not be af- 
fected by my efforts, then he has also decreed that 
mankind shall give no heed to my instructions, but 
go on in their own ways, and fulfil their appointed 

668. Again, I am told that this is making a hng 
life of more importance than a ffood life, and leads 
people to think more of the welfare of the body dian 
of the soul ; that it causes them to feel a security in 
life, and consequently to neglect their religious inter- 
ests. But these objections are wholly founded in error. 
We have seen (603) that such are the fixed constitu- 
tional relations between the animal and moral nature 
of man, and such are the fixed constitutional relations 
between man and his Creator and his fellow creatures, 
that the. true principles of health and longevity, and 
the true principles of virtue and religion, are insepar- 
able. An individual, by a correct physical regimen, 
may maintain very good bodily health, and reach an 
advanced period of life, without any true piety, and 
with very little moral virtue; so also an individual, by 
embracing correct moral and religious principles, and 
cultivating correct moral and religious sentiments, may 
attain to much virtue and piety, without a proper re- 
gard to physical regimen ; but in the former case the 
individual will come short of that perfect bodily health 



and enjoyment, and of that full duration of life; and in 
the latter case the individual will come nhort of that ele- 
vated degree of virtue and piety and happiness, which 
a full conformity to the laws of his whole nature would 
certainly secure to him. Therefore, if without any 
special regard to health and longevity, my only desire 
were to promote the highest and most perfect degree 
of virtue and piety in mankind, I would teach pre- 
cisely the same principles that I now do. The con- 
sideration of the uncertainty of life may at first serve 
to awaken our inquiries concerning our nature, our 
condition, our destiny, and our responsibilities, and 
thus to some extent be the pieans of our becoming 
virtuous and pious. But the fear of death is not in 
itself favorable to health nor long life ; neither is the 
dread of death nor the fear of punishment in itself 
virtue nor piety. The fear of hell is not the love of 
heaven, nor is the fear of Satan the love of God. It 
is only when we cherish and practice virtue because 
we love virtue, and love God because he is intrinsi- 
cally lovely, that our virtue and piety are acceptable 
to God, felicitous to ourselves, and most beneficial to 
our fellow creatures ; and all the doctrines which I 
teach are adapted to lead men to receive and obey the 
truth in the love of it, to be virtuous for virtue's sake, 
to dwell in God because he is Love ; and thus at the 
same time and by the same principles secure bodily 
health, long life, elevated virtue, and true and exalt- 
ed godliness. ' If ye know these things, happy are ye 
if ye do them.' 

669. But many say, it is not desirable to live to be 
so (dd and decrepit, and full of infirmities and ailments. 
Who, they demand, would wish to outlive their use- 
iolness and enjoyment, to lean in trembling feeble- 
ness upon the staff, to sink into the helplessness of 
second childhood, to have the senses one after another 
blotted out, and all the faculties of soul and body 
gradually decay, till we become a melancholy specta- 
cle of human frailness and imbecility, a burden to our. 
«elves and all around us, our dearest children wishing 
us in heaven? This is indeed a condition not to be 
desired ! nor is it the necessary condition of old age. 
They who make sensual enjoyment the chief end of 
their existence, and live in the continual violation 
of the laws of their nature, must of necessity either 
perish untimely by violent disease, or sink into that 
melancholy and shocking decay which is so common 
to old age. But that old age to which I would lead 
mankind is the rich and mellow autumn of our earth- 
ly existence, that period of our lives in which the 
cares and conflicts of the world are left behind, when 
all the passions are brought into subjection to a holy 
spirit, when the mind is ripe in wisdom, and the moral 
character has reached its full terrestrial maturity of 

670. We have become so accustomed to see the 
sprightliness and vivacity of childhood subside into 
the grave sobriety of mature age even before the period 
of youth has passed by, and the vigor and activity of 
meridian life wither into decrepitude and dotage long 
before a hundred years are numbered, that we have 
learned to think such things must be, and to contem. 
plate old age only as the joyless period of feebleness, 
infirmity, and exhausted powers and resources. But 
though such things are the necessary consequences of 
certain habits and circumstances of me in the present 
.«tate of the human constitution, they are neither 
Accessary nor natural to the constitution in its highest 
and Wealthiest state. 

671* In healthy childhood we see almost an exuber- 
ance of action, cheerfulness, and enjoyment ; and we 
love to. behold the sprightliness and buoyancy of that 
period. With a heart full of sympathy and delight, 
the fond parent sees his child running and leaping 
Jike the playful lamb and colt, and rejoices in the 
kappiness of his offspring ; yet before that child has 
readied the age of manhocfd, if the balrful habits and 

circumstances of civic life have not completely blighted 
all his youthful sprightliness and vivacity, he is au- 
sterely rebuked for every manifestation of them, and 
sedulously taught to smother and disguise them with 
outward sedateness and gravity, as if youthfulness of 
feeling and of action were not only improper but im- 
moral ; and if in later periods of life something of the 
buoyancy of childhood should occasionally disclose 
itsefr, it is regarded as the effect either of mental 
delirium or of some intoxicating substance. For such 
is the general stupidity of the race, that the idea of 
natural youthfulness ot feeling after man has reached 
the age of maturity, cannot be understood. 

672. But this is all wrong and unnatural, in notion 
and in fact. If sprightliness and vivacity and cheer, 
fulness be innocent and pleasing in early childhood, 
why should they not continue to be so in youth and 
manhood, and all along through life, even to the latest 
period of our earthly existence ? There is no reason 
m nature why they should not, but every vajid reason 
why they should ; and the opinion which is commonly 
entertained on this subject has sprung from sheer 
superstition growing out of the unhealthy state of 
things, and not from a sound and rational morality 
and religion. For as we have seen (603), no moral 
or civil law or religious doctrine can be adapted to the 
highest and best condition of man's moral nature, 
which is not strictly consistent with the physiological 
laws of his body, and it is entirely certain that the 
highest physiological interests of our nature require 
that youthfulness should be preserved and prolonged 
to the greatest extent. And youthfulness is as truly 
capable of being preserved and prolonged as life 
itself is, and both depend on the same means and con- 

673. I have said (634), that if there ever was a state 
of the human constitution which enabled it to sustain 
the functions of life for several hundred years, that 
state necessarily involved a general keeping or har- 
mony of relative conditions. The vital processes were 
much less rapid and intense, and much more complete 
than at present ; the development of the body was 
much slower, and the organization much more perfect ; 
childhood and adolescence were proportionately pro. 
tracted, and the change from youth to manhood took 
place at a much greater remove from birth. And 
whether the constitution be capable of a thousand or 
a hundred years of life, this keeping or harmony of 
relative conditions must always necessarily correspond 
with its capability of duration. Hence, therefore, if in 
the present state of the human constitution, we would 
aim at the longest and healthiest and happiest life, 
we can secure our object in the highest degree possible 
only b^ a strict conformity to those physiological laws 
by which youthfulness is also preserved and prolonged 
in corresponding proportion. And if by such means 
the duration of human life should, in the course of 
several venerations, be prolonged to several hundred > 
years, the period of childhood and youth would be 
proportionately protracted, and a mucn greater degree 
of youthfulness would extend through the whole dur- 
ation of our earthly pilgrimage. 

674. We have seen (124) that all organic bodies are 
composed of solids and fluids. In the earliest state of 
our existence, the human body consists mainly of flu- 
ids. * All the solids are exceedingly soft and pulpy, 
and moist or juicy. As life advances, the solids gra- 
dually become more and more consistent and compact 
and firm, and their relative proportion increases upon 
that of the fluids, until in old age as we now see it, 
they become comparatively dry and rigid, and some- 
times extremely so (185, 188, 195, 200, WJ). 

&J5, All the solids of the body, we have seen (146), 
are formed from fluids upon the most precise and deter. 

* The proportion of the fluids to Ike solidsin the adult body has 
been estixnated as ten to one. In early childhood the difference 
is much greater. 



minate constitutional principles, and there are between 
the solids and fluids the most precise and fixed con- 
stitutional relations (142) ; so that in their perfectly 
normal and healthy state, they are, in their qualities 
and susceptibilities, perfectly adapted to act on, and 
to be acted on by each other, with the most healthful 
and happy effect ; and the highest physiological and 
psychological interests of our nature can be secured 
only by uie preservation of this state of things (301). 
In this physiological condition of the system all the 
functions of life are healthfully and vigorously per- 
formed, the organic and animal sensibilities are agree- 
ably excited by their appropriate stimuli (305), the 
animal consciousness is grateful and joyous, and the 
spirits are buoyant and cheerful, lilling the whole 
body and soul with sprightliness and vivacity. 

676. In early life, when the relative proportion of 
the fluids is greatest, when the susceptibilities and 
sensibilities of the solids are most pure and delicate, 
and when the fluids and the solids are most perfectly 
adapted to each other, then also the natural activity 
and vivacity and sprightliness and buoyant cheerful- 
ness are greatest (671). The infant in its mother's 
lap delights in the constant motion of its little limbs ; 
the older child, which is able to run alone, is happy 
in continual action, and laughs aloud with instinctive 

677- If this physiological condition of the bod y could 
always be preserved, this psychological condition or 
state of the soul would always remain, and the viva- 
city and cheerfulness of youth would continue through 
life (306). But the peculiar instinctive activity of 
childhood and youth has for its final cause the full 
and vigorous development of the body. And when 
this end is effected, neither the organic nor the animal 
nor the intellectual nor moral wants of man, as an 
individual or as a social being, require that this in- 
stinctive propensity to action should continue equally 
powerful through life ; and hence, with the gradual 
changes which take place in the development and 
maturity of the body (674), this instinctive propensity 
to action gradually subsides, till instinct gives place 
to reason, and leaves the body more to the moral con- 
trol of the man, to act or rest as the wants and the 
duties of life require. But though that exuberance 
of buoyant vivacity which is the spirit of the youthful 
instinct to action, with the instinct itself, gradually 
subsides to the healthful sobriety of manhood, yet 
much of the serenity and vivacity and cheerfulness of 
youth may, and ought to, be preserved through life. 

678. In the best regulated habits and circumstances 
of life, even if all the physiological laws of the system 
are strictly obeyed, the change in the relative propor- 
tion of the solids and fluids (674) must necessarily take 
place, and with that change something of the buoyancy 
and vivacity of youth willsubsideinto the more serene 
tranquillity of mature age. But in such an obedience 
of the physiological laws of the body, this change will 
take phice very slowly, childhood and youth will be 
prolonged, the period of vigorous manhood will be 
greatly protracted, the decline of life will be very 
gradual, old age will be free from decrepitude and 
dotage, and ripe in experience and goodness; and 
much of the natural activity and vivacity and cheer- 
fulness of youth will be preserved through the whole 
of life, even to the latest period of our earthly exist- 
ence (776). 

679. Such an old age, therefore, is not only desirable 
to the individual himself, but to society at large, for 
in it man will not only retain all the physiological and 
psychological powers requisite for his own calm and 
rich enjoyment, but all which patriarchal usefulness 
in society requires. If his bodily appetites have been 
kept in subjection to physiological and moral truth 
(603), and if his intellectual and moral faculties have 
been properly cultivated, his bodily powers will be 
adequate to all the wants and duties of old age, his 

natural senses will be little impaired, his intellectaal 
and moral faculties will be vigorous and active^ the 
more ardent passions of early life will be chastened 
down, the moral man will have become wholly para- 
mount to the animal, and he will have attained to 
that maturity of wisdom and virtue which makes his 
last days the happiest period of his life, and pre-emi- 
nently fits him to commune continually in spirit with 
his God, and to exert a sanctifying influence on all 
around him. The old will reverence his counsels, 
and the young will love his society and his instruc- 

680. Such is the old age which God designed for 
man in his innocence and purity, and such is the old 
age which man is yet capable of attaining to, and 
enjoying ! *But whatsoever a man soweth, that shall 
he also reap. He that soweth to the flesh, must of 
the flesh reap corruption.* This is a solemn declar- 
ation of what, in the constitutional nature of things, 
is necessarily true, and therefore is inevitable. By 
the continued violation of the laws of life, we not only 
hasten the change in the relative proportion of the 
solids and fluids of the body (674), but yet more rapidly 
and mischievously effect a change in their relative coH' 
ditions (675), developing unhealthy susceptibilities 
and sensibilities in the solids, and filling the fluid with 
acrid and irritating properties, and thus rendering 
them wholly unfit to act on, and to be acted on, by 
each other. By these means all the physiological 
powers and functions of the body are impaired, the 
periods of childhood and youth and vigorous manhood 
are greatly abbreviated, the natural buoyancy and 
vivacity and cheerfulness of childhood and youth are 
early annihilated, and depression and sadness and 
unhappiness take their place; and disease and suffering 
and melancholy and untimely death invade every hour 
of human existence : and most of the very few who, 
through all these ills and hazards, reach a premature 
old age at seventy or eighty years, find it a period of 
feebleness and decrepitude aiid ailment and cheerless 
dotage, in which the natural senses are exceedingly 
impaired or wholly blotted out, and the intellectual 
and moral powers appear to have sunk into fearful 
and perhaps utter decay ! and all that remains of the 
living body is capable of little enjoyment in itself, and 
is the object of the painful care, and, it may be, the 
loathing, of others. 

681. The change in the relative proportion of the 
solids and fluids (674), I have said (678), must neces- 
sarily take place as life advances, even with the most 
perfect obedience to the physiological laws of the 
body ; and this change may slowly progress in per- 
fect consistency with the best of health, and with 
scarcely an appreciable abatement of natural vivacity 
and cheerfulness, from childhood to the latest hours of 
life. The more slowly and healthfully this change 
is effected, the more protracted will be the periods of 
childhood and youth and vigorous manhood, and the ' 
more gradual and healthful and happy will be the 
decline of life, and the more of youthfulness will be 
carried up through all the stages of our earthly ex- 
istence. But there is no constitutional necessity for ' 
the change in the relative corutitutions of the solids < 
and fluids of tim body (675), with which the evils I 
have spoken t0 (680) are inseparably connected. By 
a strict observance of the laws of life, these may be 
preserved in unimpaired healthfulness and purity 
from the commencement of our existence till the vital . 
functions of the system shall falter and their integ- 
rity fail from the exhaustion of the constitution m 
extreme old age. This change, so fraught with ill to |f 
man in all respects, is almost entirely the result of 
his voluntary action. The causes by which it is 
effected act on him by his own consent, though he 
may not suspect, or may deprecate, the consequences. 
It may be produced with terrible rapidity and vio- 
lence, causing the most painful and fatal disease 




(990) ; or it may be effected so gradually and by such 
imperceptible degrees as to impair all the vital powers 
and functions of the system, abbreviate the period of 
life, and bring on a premature old age, full of decrepi- 
tude and infirmity, without ever being attended with 
any violent symptoms of acute disease, and too fre- 
quently without ever being suspected as the source of 
evil to the sufferer. 

682. Whether, therefore, our object be the healthi- 
est and longest life, the happiest old age, or the most 
exalted virtue and piety, it is equally important that 
by all means in our power, we should preserve our 
natural youthfulness and vivacity and cheerfulness 
with the least possible abatement, during the whole 
of our earthly existence (675). Instead of endeavor- 
ing to suppress and subdue the youthfulness of our 
children, and to , bring them to staid maturity at 
twenty years of age, we ought to cherish their youth- 
fulness by every proper means, and endeavor to make 
them young at forty. And this is precisely the pre- 
cept of Solomon, in that passage of Scripture which 
has been so frequently and so egregiously perverted.* 
* Enjoy thy youth, O young man ! cherish and pre- 
serve the healthful cheerfulness of thy young heart, 
and be happy in the natural buoyancy and vivacity 
and sprightlmess of thy early life ! but remember, in 
all thy enjoyment, that thou art an accountable be- 
ing; that thou art under the natural and moral 
government of an omniscient, omnipotent, and infi- 
nitely wise and just God (603) ; and that thou canst 
not violate the laws of thy nature with impunity, 
nor transgress them without evil : and therefore, at 
all times carefully refrain from every indulgence and 
every pleasure by which thy youthfulness shall be 
impaired and thy soul depraved (520) ; and withhold 
thyself from all undue anxiety and labor for riches 
and honor, and all inordinate ambition and toil for 
knowledge and for renown; and from every other 
excess by which thy health will be destroyed and thy 
cheerfulness blighted and thy spirit broken, and thy 
life filled with disquietude and suffering and sorrow, 
and by which thou wilt be prematurely cut off from 
among the living, or experience a joyless old age, full 
of deerepitude and despondency and gloom ! For thy 
Creator is a God of love, and delighteth not in thy 
misery, but in thy happiness ; and mou canst not be 
permanently happy without a conformity to the laws 
of thy nature, wmch he has established in infinite 
wisdom and benevolence !' 

Ecclesiastes zi. 9. 


lAwtof constitution and relation cctablished in everjrthing: in 
the human blood, and all the substances from which it is fonn- 
ed, and which are formed from it; in and between all the 
organs of the body, and all substances designed for them to act 
on— Relations of die stomach to all organs and substances in 
the bodv ; to all alimentary substances without — No organ acts 
for itself alone — organs of external relation, primary, and 
secondary — Relations of the eye to light, and the visual pro- 

etrties of things — ^Relations of the organ of smell, to odors, etc. 
ealthy and unhealthy odors — Depravity of die olfactory sense 
—Relations of the organ of taste to gustatory properties — The 
depravity of the gustatory sense— Gustatory eajoyment greatest 
In those whose dietetic habits are most simple— Anecdote of 
the epicure— Constitutional relations of the teeth to the organs 
and substances of the body, and to the nature and condition of 
the food — Constitutional relations oi the lungs to the blood, 
etc., internally; to the atmosphere, etc., externally — Constitu- 
tional relations of the stomach to the blood, etc., internally ; 
and to all alimentary substances, externally— Its nice organic 
sensibility — This may be depraved— The consequence of this 
depravity — Relations of the stomach to the stimulating proper- 
ties of food — Relations of the stomach to the bulk or propor- 
tions of the nutritious and innutritions matter of food— Illustra- 
tions-Experiments of Dr. Stark— Relations of the sense of 
hunger to the internal wants and external supplies— Relations 
of the sense of thirst. 


683. In every part of my general argument thus 
far, I have endeavored to keep prominently in view 
the importance of the laws of constitution and the 
laws of relation, in every form of matter and mode of 
existence (140, 144). And these, I have insisted, are 
established not only in wisdom, but in benevolence 
(682), and aim as much at a result of happiness as of 
utility (603). We have seen that all the solids of the 
human body may be resolved to three general tissues 
(156) — the cellular, the muscular, and the nervous ; 
and that the vital elasticity of the cellular tissue, 
the vital susceptibility and contractility of the mus- 
cular tissue, the nervous and sensorial powers of the 
nervous tissue, together with the vital affinities 
which are under the control of the nervous power, 
constitute the grand elements of power (312), by 
which all the operations of the vital economy are car- 
ried on, and all its effects are produced. And these 
vital properties of the several tissues, in all their 
delicate modifications, of special susceptibility and 
organic and animal sensibility (292, 296), depend on 
the constitutional natures of the tissues to which 
they belong (140, 142), and every infraction of these 
laws of constitution and relation necessarily impairs 
in some degree the vital properties of the tissues, and 
functional powers of the organs composed of the 

684. We have seen, also, that the human blood has 
a fixed constitutional nature, holding a fixed relation 
to the substances from which it is elaborated (142). 
As a general statement, human blood can be elabor- 
ated from all vegetable and animal substances ; every 
moving thing diat liveth, as well as every green herb 
or vegetable, can be made meat for man ; but the 
vital constitution and properties of the blood nicely 
vary with the varying qualities of the food; and 
hence the blood holds a fixed and precise constitu- 
tional relation to the particular kinds of substances 
on which man can subsist ; and consequently, the 
vital constitution and properties of the blood are more 
or less perfectly adapted to the final causes of ouv 
organization, and to the highest and best condition 
of human nature, according to the character of the 
particular substances on which we subsist. If, there- 
fore, our food is not what it should be, our blood as a 
genera] and permanent fact, cannot be what it should 
be. It is true, that while the assimilating powers of 
the vital economy are vigorous and unimpaired, a 
considerable integrity of functional results may be 
maintained by that economy, for a longer or shorter 
time, even though the alimentary substances from 
which it elaborates the blood are not best adapted to 
the wants of the system ; yet such substances neces- 
sarily in a greater or less degree impair the assimi- 
lating powers of the vital economy, and in the end 
deteriorate the functional results. 

685. Again, each of the scdids and fluids of the 
human system, formed from the blood, has a fixed 
constitutional nature (142), holding fixed and precise 
relations to the blood and to each other, so that if the 
blood is not what it should be, these cannot be what 
they should be. The cellular, the muscular, and 
nervous tissues cannot be produced by the vital eco- 
nomy from anything else than true animal blood, 
and therefore each of these tissues has not only a 
fixed constitutional nature peculiar to itself, but ne- 
cessarily also a fixed and precise constitutional rela- 
tion to the constitutional nature of the blood, and 
through the blood to the substances from which the 
blood is elaborated ; and as they are all produced by 
one and the same vital economy from one and the 
same current of blood (497), they necessarily hold 
fixed relations to each. 

686. The vital properties of the tissues (312) in aU 
their delicate modifications, depending on the consti- 



tutional nature of the tissues (683), necessarily hold 
fixed and precise relations to the constitutional nature 
of the blood ; so that these properties always nicely 
▼ary with the varying character of the blood ; and 
hence, whatever deteriorates the constitutional nature 
of the blood, necessarily, as a general fact, impairs 
the vital elasticity of the cellular tissue, the vital 
susceptibility and contractility of the muscular tissue, 
and the nervous and sensorial powers of the nervous 
tissue, in all their delicate modifications : and, on 
on the other hand, whatever impairs the vital pro- 
perties of the tissues, necessarily, as a general fact, 
deteriorates the constitutional nature of the blood. 
Constitutional relations equally determinate exist 
between all the fluids of the system, and between the 
fluids and the solids (675). 

687. Such ate the laws of constitution and relation 
which a wise and benevolent Creator has established 
in and between all the particular substances of which 
our bodies are composed ; and hence, of necessity, 
the constitutional and functional laws of relation be- 
tween all the organs of the system, and between each 
of these and each and all the particular substances of 
which our bodies are composed, are equally precise 
and determinate. Thus, the stomach is organized 
with fixed and precise relations to all the other organs, 
and to the blood and every other substance of the 
body ; and the functions of the stomach necessarily 
hold fixed and precise relations to the blood, and to 
all the other substances of the body, and to the func- 
tions of all the other organs ; and all this is true of 
each and every other organ of the system. Each 
organ has its particular function to perform, yet no 
organ can perform its function independently of the 
others, and no organ can sustain itself by its own 
function : on the contrary, each organ exhausts its 
vital powers and wastes its substance by the perform- 
ance^ of its own particular function (376), and is re- 
plenished and nourished and sustained by the united 
functions of the whole assemblage of organs. The 
alimentary canal (320) digests food for the whole sys- 
tem ; the lacteals (388) elaborate chyle for the whole 
system ; and the liver and kidneys and blood-vessels 
and lungs and skin perform their functions for the 
whole system ; and therefore, the function of no one 
organ can be impaired, without involving the whole sys- 
tern in the consequences. Such is the dependence of 
each organ upon the whole system, and of the whole 
system upon each organ ; and such are the fixed and 
important laws of constitution and relation apper- 
taining to the internal economy of the human body 

688. But the human body subsists on foreign sub- 
stances (209), or materials which are extrinsic and 
separated from itself; and therefore it is furnished 
With organs of external relation (210), which are con- 
stituted with fixed and precise relations to the consti- 
tutional nature of the blood, and to all the other sub- 
stances of which the body is composed, and with fixed 
and precise relations to the constitutional nature of 
the external substances designed for the nourishment 
of the body. The primary organs of this class are 
the alimentary canal, the lungs, and the skin ; and 
for the supply of the wants of the vital economy, and 
the protection of the vital welfare, we are furnished 
with organs of external perception, of locomotion, 
and of prehension (233). The organs of external 
perception are those of touch, taste, smell, hearing, 
and sight. The organs of locomotion are the lower 
extremities, or the legs and feet. The organs of pre- 
hension ate the upper extremities, or the arms and 


689. The organs of sight (409, et. aeq,) are consti- 
tuted with the most precise and fixed relations to the 

constitutional nature of li^ht, and to those properties 
of external things of which light is the medium of 
perception (554) ; so that when the organs are in a 
perfectly normal state, and the light is pure and per- 
fectly natural, we have a perfect visual perception of 
all external objects to which the eye is directed : but 
whatever impairs the constitutional nature of the 
organs, necessarily impairs their visual powers, and 
the visual perception of external things is cominen- 
surately less perfect : and hence whatever impairs the 
sensorial powers of the nervous system, necessarily 
impairs our visual powers (1126). But we have seen 
that there are fixed and precise constitutional rela- 
tions between all the tissues (685) and substances of 
the body; and therefore whatever deteriorates the 
constitutional nature of any of the tissues of the body 
(686), as a general fact, impairs the visual powers of 
our organs of sight ; and all this is true of the organs 
of hearing, smell, taste, and touch. 

690. The organs of smell (398) and taste (397) are 
more especially the instruments of instinct employed 
in the functions of respiration and alimentation, as 
sentinels on the out-posts of the vital domain. Every 
vegetable and animal substance, and many inorganic 
substances, possess specific properties in relation to 
animal life, and to the wants of the vital economy of 
animal bodies. Some of these are salutary and some 
are baneful ; and each of these substances imparts an 
odor to the surrounding atmosphere, exactly charac- 
teristic of its specific properties. Our organ of smdl, 
therefore, is constituted with fixed and precise rela- 
tions to the constitutional nature of the blood and 
other substances of the body, to the general wants of 
the vital economy, to the organization and functional 
powers of the lungs and stomach within, and with 
fixed and precise relations to the qualities of odors 
without. So that, in aperfectly normal andundepraved 
state of the organ, it detects the qualities of odors 
with the nicest accuracy, and unerringly discrimi- 
nates between what is good or salutary for the living 
body, and what is baneful or injurious. Physiolo- 

gists, judging from the depraved condition of the 
uman organs, universally assert that the instinctive 
power of smell is naturally far less keen and discrimi- 
nating in man than in many of the lower animals. 
But this is entirely incorrect. Reasoning a priori, 
from the nature of things, we should be led to conclu- 
sions different from the doctrine of the schools on this 
subject ; and we know from the most complete expe- 
riment, that were the human species reared, from 
birth to maturity, in as strict accordance with the 
constitutional laws of their nature, as are the lower 
animals in a pure state of nature, the faculty of smell 
in man would at least equal, and probably far excel, 
that of any other animal, in exquisite delicacy of per- 
ception and in discriminating power, for the instinct- 
ive purposes of the system. It would enable us with 
unerring accuracy to select or to avoid instinctivdy 
whatever is salutary or baneful, whatever is bene- 
ficial or injurious to us, in those qualities of things 
appreciable by smell. And, therefore, the faculty 
was given to us not only as a means of enjoyment, 
but pre-eminently to serve the instinctive purposes of 
the vital economy (596) in detecting the specific cha- 
racters of external things in relation to life, by the 
odors which they impart.* 

691. The organ of smell is a sentinel for both the 
lungs and the alimentary canal. It is of the utmost 
importance to the vital welfare of the body, that pure 
air should be constantly received into the lungs at 
every inspiration of breath ; and hence the olfactory 
nerves are distributed over the lining membrane m 
the cavities of the nose (399), through which the air 

* It is a remarkable fact, according to both Soemmeiring and 
Blamenbach, that the organ of smell is smaller in the civiliMd 
portions of the human family than in those who are little removed 
nom the savage state. 



passes into the lungs ; and when in a perfectly healthy 
and undepraved state^ they detect, with the nicest 
powers of discrimination and integrity of instinct, 
every odorous property of the atmosphere which is 
unfriendly to life; and the animal being thus in- 
formed of the presence of an unwholesome atmosphere, 
is able to suspend respiration for a very short time 
(902), and to hasten from the offending cause. 

692. It is not only true that some odors are in 
themselves baneful to the human body when received 
into the lungs in any quantity, but it is also true that 
odors which are themselves innoxious and delightful 
when properly diluted with pure air, become exceed- 
ingly oppressive and even dangerous to us when too 
mncn concentrated, or when the air which we breathe 
is too deeply freighted with them. Thus, a person 
whose system is pure and whose olfactory nerves are 
perfectly healthy and undepraved, will feel a severe 
nervous oppression accompanied with more or less 
pain in the head, flush of the face, quickened pulse, 
general symptoms of fever attended with chills, and 
perhaps followed by profuse perspiration, if he breathes 
for a short time the air which is loaded with the per- 
fumes of a garden of roses and other flowers, or the 
air of a room containing several pots of geranium.* 
And, therefore, while the natural distribution of 
flowers and fragrant herbs over the face of the earth 
imparts a healthful perfume to the atmosphere, af- 
fording us a rich enjoyment in the exercise of our 
sense of smell, and evincing the goodness as well as 
the wisdom of the Creator, the cultivating and crowd- 
ing of large numbers of fragrant flowers and plants 
together in gardens and houses is decidedly unfriendly 
to the physiological welfare of our bodies. So true is 
it that an infinitely wise and benevolent God has cre- 
ated us with such a nature, and established in our 
nature such constitutional relations to external things, 
that, while we have high and healthful enjoyment 
in the proper exercise of all our faculties and powers, 
we cannot make the gratification of any of our senses 
a source of enjo3anent beyond the fulfilment of the 
constitutional purposes for which those senses were 
instituted, without jeoparding all the interests of our 
nature, and finding disease and suffering in our pur. 
suit of happiness. 

693. But some will say that such an exquisitely 
delicate power of smell is far from being desirable ; 
that they would not wish to possess such keen olfac- 
tory sensibility as to feel oppressed and pained by the 
rich fragrance of a flower garden, and the delightful 
breath of the domesticated geranium. Yet let them 
remember, that by divesting themselves of this sensi- 
bility, they do not alter the constitutional relations 
between the odors which they breathe and the vital 
properties and interests of their bodies ! Whether 
the olfactory sentinel which a wise and benevolent 
God has placed on the outposts of the vital domain 
performs with strict integrity the duties for which 
It was placed there, or not, still the properties which 
the inspired air carries into the lungs are equally 
salutary or baneful to the vital interests of the body. 
Let them remember also, that by divesting themselves 
of that exquisitely delicate sensibility of the olfactory 
nerves which renders them unable to inhale the air 
that is too deeply loaded with the fragrance of a 
flower garden without oppression and pain, they 
thereby necessarily divest themselves of that nice 
olfiu^ry power with which God has endowed them, 
to discriminate instinctively between salutary and 
poisonous odors and substances. Thus, like the re- 
bellious Israelites in the wilderness, they drive away 
that spirit of truth with which God had endowed 
their organs, to guide them in the way of life and 
health and happiness, and yielding themselves up to 

I * Many indiiridaals have died luddenly in consequence of in- 
spiring the too powerful perAime of roies and other fragrant 
flowety accumulated in large quantities. 

their sensualities, they sink deeper and deeper in de- 
pravity, till they learn perhaps to find their greatest 
delight in breathing the most poisonous odors of the 
vegetable kingdom ; and receive their deadliest enemy 
into their bosom as their dearest friend, without the 
slightest suspicion of their danger ; and millions per- 
ish with every form of disease and suffering, cherish- 
ing with unbounded confidence to the last moment, 
as their most tried friend and greatest comforter, the 
very enemy that thus treacherously destroys their 
lives. It were infinitely more wise, then, to cherish 
the strictest integrity of those sentinels which God, in 
wisdom and in goodness, has established for the pro- 
tection of our vital interests, and to obey their holiest 
dictates, and shun or remove whatever offends them, 
than to destroy their integrity, that we may feel 
secure in the presence of our enemies, and revel in 
unsuspecting confidence in the midst of danger. 

694. Besides thus acting as sentinel to the lungs, 
to protect them from impure air, the organ of smell, 
as I have stated (691), is also, in its perfectly healthy 
and undepraved state, a sentinel to the alimentary 
canal (294), and enables us instinctively, with uner- 
ring accuracy, to discriminate between those sub- 
stances which are salutary and proper for our nou- 
rishment, and those which are poisonous or unsuitable 
to be introduced into the stomach.* But this sentinel 
may be so depraved as to lose its discriminating 
power, and be no longer able to detect the baneful 
qualities of things, and thus become wholly unfitted 
to answer the instinctive purposes of the system. 
Indeed, it may become so excessively depraved as 
entirely to lose the power of appreciating odors ; in 
which case the organ will only retain the ability to 
appreciate the degree of stimulation, without the 
least power to appreciate the quality of the stimulus. 
Thus, snuff-takers always exceedingly deprave the 
sense of smell, and greatly impair, and often wholly 
destroy, its power of discriminating between odors of 
the most opposite character ; and in some instances 
the power of smell is completely destroyed, and the 
organ only retains the ability to appreciate the stimu- 
lation of the most powerful stimuli. In such cases, 
the parts to which the stimulus is applied, and those 
which are associated with them, become so accustomed 
to, and so dependent on, the artificial stimulus for 
their wonted excitement, that the natural and appro- 
priate stimuli of the system are wholly inadequate to 
save them from that deep and distressing prostration 
which necessarily results from their habitual and 
shocking debauchery ; and therefore they become ex- 
ceedingly eager, and even vehemently importunate, 
in their demands for the artificial stimulus, and will 
not be pacified without it. Hence the power of such 
habits, and the great difficulty of breaking them up. 

695. To preserve the natural purity and functional 
powers and integrity of the organ of smell, and to 
prevent the depravity which I have described, the 
sensibilities of the organ and the sympathies of the sys- 
tem unite to resist the encroachments of all depraving 
and offending causes. Numerous filaments of the 
trifacial nerve (254, 255, 256) are distributed over 
the lining membrane of the cavities of the nose, 
where thev are intimately associated with the fila- 
ments of tte olfactory, or special nerve of smell. The 
olfactory nerve possesses no sensibility except that 
which perceives odors. The common' sensibility or 
feeling of the nasal cavities, therefore, is whoUy the 

* ' Without the aid of smell, the sense of taste would be very 
vague in its indications and limited in its range,' says Professer 
Roget; and such is the prevailing opinion of physiologists; and 
yet Mr. Hill, who has not been able to smell even the most pun- 
gent odors for the last ten years (see Note to 563), assures me that 
his sense of taste remains good and nicely discriminating in all 
gustatory qualities ; but he finds, since he lost his smell, that he 
used often to confound gustatory with olfactory perception in his 
mind, and suppose he tasted qualities which in reality he smelt. 
This is undoubtedly a common enor. 



property of the filaments of the trifacial. These fila- 
ments liare not in the slightest degree the power of 
perceiving odors ; but so intimately connected in 
anatomical arrangement and functional relation are 
they with the olfactory nerve, that their healthy sen- 
sibility cannot be impaired without detriment to the 
sense of smell, and jeopardy to the whole system. 
Hence, when any substance comes in contact with 
the lining membrane of the cavities of the nose, 
which is of a nature to impair the sense of smell, 
to injure the lungs, or to impair the vital properties 
of the trifacial nerve, or in any manner to jeopard 
the interests of the vital economy, the trifacial nerve 
instantly feels the presence of the substance, and the 
membrane is excited to an increased secretion of 
mucus to shield the parts (339) from its poisonous or 
irritating properties ; and if the offending cause is 
of such importance, either in quality or quantity, as 
considerably to endanger the system or the parts on 
which it acts, the trifacial nerve immediately gives 
a sympathetic alarm, which is instantly diffused over 
the domain of organic life (225), and the instinctive 
powers of the system are at once called up to expel 
the invading foe. A deep, full breath is inhaled, and 
then the arch of the tongue is raised and pressed 
against the veil of the palate so as to prevent the air 
from passing out at the mouth, and the diaphragm, 
and the abdominal muscles which draw down the 
breast-bone and ribs, are suddenly and powerfully 
contracted, and the air of the lungs is violently driven 
out through the cavities of the nose, for the purpose 
of expelling the offending cause. 

696, Thus, if a person with a pure system and un- 
depraved olfactory nerves, comes into the vicinity of 
a large quantity of tobacco, he instantly perceives the 
loathsome odor, and at once detects its poisonous 
character, and finds himself urged by many distress- 
ing feelings to avoid the deadly narcotic; but if, 
regardless of these admonitions, he thrusts some pow- 
dered tobacco into his nose, his olfactory nerve still 
perceives and appreciates the poisonous odor, and the 
trifacial nerve feels the poisonous character of the 
irritating substance, and gives the alarm to the 
domain of organic life, and violent sneezing soon en- 
sues as the instinctive means of expelling the offend- 
ing cause. If the offending cause is not removed by 
sneezing, the whple system soon becomes so much 
affected by the poison, that the most distressing diz- 
ziness, and muscular relaxation and tremor and sick- 
ness at the stomach, and cold sweat, and vomiting 
and convulsions, follow in rapid succession, in order 
both to expel the poison from the vital domain, and 
to cause us ever after more cautiously to avoid so 
deadly and so foul an enemy. But by commencing 
thi& career of depravity with cautiously measured 
steps at first, we may in time succeed in utterly des- 
troying the integrity of this important sentinel, and 
so completely deprave both the olfactory nerve and 
the nasal portion of the trifacial, that neither of them 
can any longer detect the poisonous character of the 
tobacco, but both of them will become so adapted to 
its properties, as to delight in its stimulation, with an 
intensity of morbid enjoyment equal to the depth of 
depravity to which they are reduced. And thus the 
organ of smell, instead of guarding the vital domain 
like a true and faithful sentinel, against the encroach- 
ments of every enemy which it is naturally qualified 
to detect, not only ceases to give alarm to that domain 
when those enemies are approaching, but even throws 
open its gate and earnestly entreats those enemies to 
enter, and embraces the foulest and the deadliest of 
them all as the dearest and most valuable friend, and 
ushers it into the vital domain, proclaiming with 
inebriated energy the introduction of a generous and 
glorious conservator. And thus, by sensual depra- 
vity, we transform a guardian angel of light into a 
treacherous demon of darkness ; and still confiding 

in its integrity and fidelity to the vital domain, we 
receive into the very citadel of life the enemy which 
poisons all our wells of vitality, and with perfect in« 
fatuation rejoice in his destructive influence, and 
regard his witheri